Researcher basic information

• Ph. D, The University of Tokyo

• https://researchmap.jp/read0073202?lang=en

• https://jglobal.jst.go.jp/detail?JGLOBAL_ID=200901077833421345
• https://wwwchem.sci.hokudai.ac.jp/~qc/member/tetsuya-taketsugu/
• https://wwwchem.sci.hokudai.ac.jp/~qc/en/member/tetsuya-taketsugu/

• 200901077833421345

• quantum chemistry
• Reaction Dynamics
• Computational Chemistry
• Theoretical Chemistry

• Nanotechnology/Materials, Fundamental physical chemistry, Theoretical Chemistry

• Bachelor's degree program, School of Science
• Master's degree program, Graduate School of Chemical Sciences and Engineering
• Doctoral (PhD) degree program, Graduate School of Chemical Sciences and Engineering

Research activity information

• Sep. 2024, Japan Society for Molecular Science, The 15th Award of the Japan Society for Molecular Science
  Deepening the Understanding of Chemical Reaction Dynamics Based on the Concept of Reaction Pathways
  Tetsuya Taketsugu
• Feb. 2021, Hokkaido University, The Hokkaido University President’s Award for Excellence in Research and Education for AY2020
  Tetsuya Taketsugu
• Mar. 2019, The Chemical Society of Japan, The CSJ Award for Creative Work
  Ab Initio Elucidation of Electronically-Excited Reaction Processes and Dynamics
  TAKETSUGU Tetsuya

• Computational Insights into the Revised Mechanism of the Gold-Catalyzed Asymmetric Isocyanoacetate Aldol Reaction: Proton Shuttling and Protonative Carbonyl Activation under Ligand–Substrate Interactions
  Kosuke Higashida; Chiaki Koike; Taichi Shomura; Shinnosuke Sunazaki; Takuma Ito; Yu Harabuchi; Tetsuya Taketsugu; Satoshi Sakai; Yohei Shimizu; Satoshi Maeda; Masaya Sawamura
  ACS Catalysis, American Chemical Society (ACS), 15 Jul. 2026, [Peer-reviewed], [International Magazine]
  Scientific journal
• Orbital energy variations provide a physical basis for the Woodward-Hoffmann rules
  Masaya Tsuruta; Tsuyoshi Mita; Tetsuya Taketsugu; Takao Tsuneda
  Scientific Reports, Springer Science and Business Media LLC, 14 Jul. 2026, [Peer-reviewed], [International Magazine]
  Scientific journal
• Spin-Projected Divide-and-Conquer Unrestricted Self-Consistent Field: Practical Linear-Scaling Approaches for Static Correlation
  Takeshi Yoshikawa; Sousei Kasaya; Masatsugu Nishida; Tetsuya Taketsugu; Masato Kobayashi
  Journal of Chemical Theory and Computation, American Chemical Society (ACS), 09 Jul. 2026, [Peer-reviewed], [International Magazine]
  Scientific journal
• Crystal-environment control of excited-state reaction branching in 5-chloro- N -salicylideneaniline
  Hiroto Komuro; Kenichiro Saita; Takuro Tsutsumi; Tetsuya Taketsugu
  Physical Chemistry Chemical Physics, Royal Society of Chemistry (RSC), 06 Jul. 2026, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal, Reaction-path analysis and AIMD show that crystal packing reshapes the excited-state dynamics of 5-chloro- N -salicylideneaniline. In the planar β-phase, both the competing C–N twist channel and the post-ESIPT C–C twisting are suppressed.
• Faradaic control of adsorbate coverage during thermal catalytic hydrogenation of small unsaturated carboxylic acids
  C.-K. Hung; K. Obata; A. Lyalin; T. Taketsugu; K. Takanabe
  ACS Catal., Jul. 2026, [Peer-reviewed], [International Magazine]
• Mapping the Product-Dividing Boundary from a Valley-Ridge Inflection to the Product-Connecting Transition State in Substituent-Controlled Bifurcating Reactions
  J. Suzuki; T. Nakanishi; R. Kambara; Y. Ono; T. Tsutsumi; T. Taketsugu
  J. Chem. Theory Comput., Jul. 2026, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
• Antenna Tuning in Photoredox Nitric Oxide Releasers for Potent Photovasodilation
  Daisuke Saitoh; Sae Kitamura; Naoya Ieda; Kyoya Oyama; Yuhei Ohta; Yuji Hotta; Masato Kobayashi; Mei Harada; Mikako Ogawa; Mitsuyasu Kawaguchi; Kazunori Kimura; Tetsuya Taketsugu; Hidehiko Nakagawa
  Journal of Medicinal Chemistry, American Chemical Society (ACS), 11 Jun. 2026, [Peer-reviewed], [International Magazine]
  Scientific journal
• Hydrogen‐Assisted Ring Opening of Methylcyclohexane on Pt(111) and Ir(111): A Comparative Theoretical Study of the Reaction Mechanism
  Esackraj Karthikraja; Andrey Lyalin; Sonu Kumar; Takashi Nakano; Tetsuya Taketsugu
  ChemCatChem, 18, 10, e01862, Wiley, 18 May 2026, [Peer-reviewed], [Invited], [Last author, Corresponding author], [International Magazine]
  Scientific journal, ABSTRACT
  
  Ring‐opening reactions over noble‐metal catalysts show a strong dependence on the metal, but the mechanistic origin of the different behavior remains poorly understood. In this theoretical study, we investigated the hydrogen‐assisted hydrogenolysis mechanism for the ring‐opening of methylcyclohexane, together with the associated product selectivity, by analyzing the relevant mechanistic pathways on iridium (Ir) and platinum (Pt) surfaces, which are commonly used catalysts for hydrocarbon hydrogenolysis. The calculated activation barriers reveal that Ir(111) consistently exhibits lower C─C cleavage barriers than Pt(111) across all pathways, in agreement with experimental observations. To elucidate the origin of this difference, we analyzed the catalytic activity on Ir(111) and compared it with Pt(111). The results demonstrate that surface‐bound hydrogen plays a decisive role in facilitating the C─C hydrogenolysis step. Moderate hydrogen binding on Ir(111) enables efficient hydrogen transfer along the reaction pathway, whereas stronger hydrogen binding on Pt(111) restricts hydrogen mobility and reduces its participation in C─C cleavage. Overall, this comparative study provides valuable insights into the superior ring‐opening performance of iridium catalysts and highlights the critical role of surface hydrogen energetics in determining catalytic activity.
• Local structures and catalytic N2O decomposition properties of Ni1−xCuxCo2O4
  Satoshi Hinokuma; Nino Uchiyama; Tetsuya Taketsugu; Takeshi Iwasa
  Scientific Reports, 16, 1, Springer Science and Business Media LLC, 21 Apr. 2026, [Peer-reviewed], [International Magazine]
  Scientific journal
• Nanointerface Coupling Activates Earth-Abundant Elements for Enhanced Oxygen Evolution Electrode Process
  Miao Wang; Wenqin Peng; Andrey Lyalin; Nattamon Suwannaharn; Takuya Tsuji; Daiju Matsumura; Tetsuro Morooka; Tomoaki Kumeda; Tetsuya Taketsugu; Tadakatsu Ohkubo; Takuya Masuda; Taisuke T. Sasaki; Ken Sakaushi
  The Journal of Physical Chemistry C, 130, 2, 931, 941, American Chemical Society (ACS), 31 Dec. 2025, [Peer-reviewed], [International Magazine]
  Scientific journal
• ChemOntology: A Reusable Explicit Chemical Ontology-Based Method to Expedite Reaction Path Searches
  Pinku Nath; Yuriko Ono; Yu Harabuchi; Yasunori Yamamoto; Satoshi Maeda; Tetsuya Taketsugu; Masaharu Yoshioka
  ACS Catalysis, 16, 2105, 2118, American Chemical Society (ACS), 21 Dec. 2025, [Peer-reviewed], [International Magazine]
  Scientific journal
• Ground-and excited-state fragmentation dynamics of doubly ionized OCS: A theoretical study
  Ryuto Kambara; Takuro Tsutsumi; Kenji Furuya; Tetsuya Taketsugu
  The Journal of Chemical Physics, 163, 22, 224303, AIP Publishing, 08 Dec. 2025, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal, We investigated fragmentation dynamics of OCS2+ after photoinduced double ionization by combining static potential energy surface (PES) analysis with ab initio molecular dynamics (AIMD) and surface-hopping AIMD (SH-AIMD). In the ground state, AIMD shows that the isomerization pathway from OCS2+ to COS2+, although accessible on the static PES, is dynamically hidden. Trajectories rarely follow it because it requires unrealistically high bending excitation, whereas S+ dissociation proceeds without such a constraint. Consequently, energy released upon ionization is funneled more efficiently into dissociation, favoring S+ dissociation over isomerization. For excited states, SH-AIMD trajectories launched from the lowest triplet 3Π states and the 23Δ state reproduce the observed fragmentation: predominant S+ dissociation with minor O+ formation. The isomerization process leading to the COS2+ structure was not observed in the simulations. These results are consistent with experimental observations. Notably, for the O+ channel, we likely achieve the first AIMD reproduction of the experimental appearance threshold using only triplet states and no external laser fields. This indicates that vibronic coupling via bending motion is essential to enable O+ release, although its probability remains small relative to S+ dissociation. Overall, fragmentation in OCS2+ is governed by the interplay of vibronic coupling and dynamical effects: bending vibrations can facilitate O+ release, whereas isomerization to COS2+ is dynamically suppressed by the requirement of extreme bending excitation. The high density of states in the excited manifold further underscores the strongly nonadiabatic character of OCS2+. Our results connect static PES features with trajectory-based dynamics, offering new insight into selective fragmentation in polyatomic dications.
• Doublet Charge Transfer Emission of Cerium(III) Complexes with Strong Electron-Accepting Ligands
  Toranosuke Tomikawa; Kenichiro Saita; Yuriko Ono; Tomoko Akama; Mengfei Wang; Sunao Shoji; Masato Kobayashi; Koji Fushimi; Takayuki Nakanishi; Tetsuya Taketsugu; Yasuchika Hasegawa; Yuichi Kitagawa
  The Journal of Physical Chemistry Letters, 16, 49, 12655, 12660, American Chemical Society (ACS), 04 Dec. 2025, [Peer-reviewed], [International Magazine]
  Scientific journal
• Divide‐And‐Conquer Extended Tight‐Binding Molecular Dynamics: A General‐Purpose, Very Large‐Scale Quantum Molecular Dynamics Method
  Masatsugu Nishida; Kotaro Fujiwara; Tetsuya Taketsugu; Masato Kobayashi
  Journal of Computational Chemistry, 46, 28, e70255, Wiley, 24 Oct. 2025, [Peer-reviewed], [International Magazine]
  Scientific journal, ABSTRACT
  
  We have combined the linear‐scaling divide‐and‐conquer (DC) method with the semi‐empirical extended tight‐binding (xTB) method to develop a general‐purpose large‐scale quantum molecular dynamics simulation platform called DCxTBMD. Although the DC method is a fragmentation‐based acceleration scheme, it is possible to perform highly accurate calculations even when adopting formal grid‐based fragmentation, thanks to the mechanism called the buffer region. The program was developed by incorporating xTB Hamiltonian construction modules in the xTB program into the DCDFTBK package, a DC‐based density functional tight‐binding (DFTB) calculation suite. The accuracy and computational time, including the parallel scalability, of the present method were investigated on the Japanese supercomputer Fugaku, and it was found that the present method is suitable for the efficient calculation of large systems, including multiple heteroelements. We further implemented the energy gradient of the present method to enable the molecular dynamics simulation of such systems.
• Substituent Effects on Electrocyclic Reactions: Ultrafast Ring-Opening of α-Phellandrene Stimulated by Impulsively Excited Molecular Vibrations
  Zhiyi Zhou; Kenichiro Saita; Yusuke Minegishi; Tetsuya Taketsugu; Taro Sekikawa
  The Journal of Physical Chemistry A, 129, 38, 8733, 8743, American Chemical Society (ACS), 16 Sep. 2025, [Peer-reviewed], [International Magazine]
  Scientific journal
• Predicting Catalytic Activity for CH4 Combustion on Pd-exchanged Zeolite Catalysts Using Automated Reaction Route Mapping
  Shiho Sakuma; Shunsaku Yasumura; Kenichiro Saita; Tetsuya Taketsugu; Masaru Ogura
  J. Phys. Chem. C, 129, 18004, 18010, Sep. 2025, [Peer-reviewed], [International Magazine]
  English
• Unraveling the structural origins of stimulated emission redshift in cyanine dye 1122C: a combined AIMD and machine learning study
  Yusuke Minegishi; Kenichiro Saita; Takuro Tsutsumi; Tetsuya Taketsugu
  Physical Chemistry Chemical Physics, 27, 37, 19868, 19876, Royal Society of Chemistry (RSC), 27 Aug. 2025, [Peer-reviewed], [Invited], [Last author, Corresponding author], [International Magazine]
  Scientific journal, 1122C undergoes ultrafast trans – cis photoisomerization, but its excited-state dynamics remain unclear. AIMD reproduces the stimulated emission (SE) spectrum. Using machine learning, we identified structural deformations driving SE redshift.
• Tracking electron motion driving the Suzuki–Miyaura cross-coupling reaction
  Noriyuki Takai; Takuro Tsutsumi; Tetsuya Taketsugu; Takao Tsuneda
  Physical Chemistry Chemical Physics, 27, 33, 17261, 17269, Royal Society of Chemistry (RSC), 30 Jul. 2025, [Peer-reviewed], [Invited], [International Magazine]
  Scientific journal, The electron motion driving the transmetalation process of the Suzuki–Miyaura cross-coupling reaction is elucidated based on the reactive orbital energy theory (ROET).
• Homoleptic copper(i)–bisphosphine complexes as photoredox catalysts
  P. Saha; R. Tomita; T. Tsuneda; P. Jiang; T. Taketsugu; M. Jin; D. C.-Y. Huang
  Dalton Trans., 54, 30, 11725, 11731, 17 Jul. 2025, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Aggregation-induced emission mechanism of styrene derivative: a theoretical study
  Aarzoo; Kenichiro Saita; Masato Kobayashi; Takao Tsuneda; Tetsuya Taketsugu; Ram Kinkar Roy
  Physical Chemistry Chemical Physics, 27, 12593, 12602, Royal Society of Chemistry (RSC), 28 May 2025, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal, The AIE mechanism of the styrene derivative 4-dimethylamino-2-benzylidene malonic acid dimethyl ester (BIM) in methanol solution is theoretically investigated using SF-LC-TDDFT.
• Theoretical Study of Near-Field-Induced Local Excitation Dynamics
  Daisuke Nishizawa; Tetsuya Taketsugu; Takeshi Iwasa
  Chemistry Letters, 54, 6, upaf109, Oxford University Press (OUP), 23 May 2025, [Peer-reviewed], [Invited], [International Magazine]
  English, Scientific journal, Abstract
  
  Near-field optics provides a revolutionary pathway to achieve high spatial resolution beyond the diffraction limit, which is unattainable with conventional optics. Furthermore, the strong localization of near-field light induces spatially non-uniform interactions with molecules, enabling access to forbidden quantum states and allowing for the control of light at the single-molecule level. To describe such non-uniform interactions between near-field light and molecules, we have developed a theoretical framework that goes beyond the dipole approximation. In this highlight review, we present the theoretical and computational frameworks developed primarily based on the multipolar Hamiltonian, along with a recent study that explores the electron dynamics of a single molecule induced by near-field excitation.
• Theoretical Insights into Ultrafast-Decaying and Long-Lived States of ortho-Nitrophenol upon Photoexcitation in the Gas Phase
  Satoi Wada; Takuro Tsutsumi; Kenichiro Saita; Taro Sekikawa; Tetsuya Taketsugu
  The Journal of Physical Chemistry Letters, 16, 21, 5373, 5380, American Chemical Society (ACS), 21 May 2025, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Bridging electron and nuclear motions in chemical reactions through electrostatic forces from reactive orbitals
  Takao Tsuneda; Tetsuya Taketsugu
  Communications Chemistry, 8, 1, 158, Springer Science and Business Media LLC, 19 May 2025, [Peer-reviewed], [Last author], [International Magazine]
  English, Scientific journal
• Unraveling Reaction Path Bifurcation: Insights Into Electron Movement via Natural Reaction Orbitals
  Tatsuhiro Nakanishi; Takuro Tsutsumi; Yuriko Ono; Kazuki Sada; Tetsuya Taketsugu
  Journal of Computational Chemistry, 46, 10, e70101, Wiley, 11 Apr. 2025, [Peer-reviewed], [Invited], [Last author, Corresponding author], [International Magazine]
  Scientific journal, ABSTRACT
  
  This study investigates the Beckmann rearrangement of 1‐phenyl‐2‐propanone oxime derivatives, focusing on the reaction path bifurcation behavior from the perspective of electron movement. The previous work reported that electron‐withdrawing substituents drove the reaction toward the rearrangement pathway, while electron‐donating substituents favored the fragmentation pathway. Through natural reaction orbital (NRO) analysis, this research demonstrates how electrons move at critical branching points, specifically in the directions of the intrinsic reaction coordinate (IRC) and the projected vibrational mode associated with the branching behavior. The NRO approach, which complements traditional IRC and ab initio molecular dynamics methods, not only provides valuable quantitative insights for predicting product distributions but also aids in the strategic design of substituents for desired products. These findings extend our understanding of reaction mechanisms and byproduct formation, offering fresh perspectives on complex chemical transformations.
• Enhancing the oxygen evolution reaction by tuning the electrode-electrolyte interface in nickel-based electrocatalysts
  Ben Wang; Tomohiro Fukushima; Hiro Minamimoto; Andrey Lyalin; Kei Murakoshi; Tetsuya Taketsugu
  COMMUNICATIONS CHEMISTRY, 8, 1, 109, 08 Apr. 2025, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Dynamics of Doubly Ionized OCS Molecules and Hidden Reaction Pathways
  Ryuto KAMBARA; Takuro TSUTSUMI; Kenji FURUYA; Tetsuya TAKETSUGU
  Journal of Computer Chemistry, Japan, 24, 1, 5, 9, Society of Computer Chemistry Japan, 29 Mar. 2025, [Peer-reviewed], [Invited], [Last author, Corresponding author], [Domestic magazines]
  Japanese, Scientific journal
• A nearly perfect icosahedral Ir@Au₁₂ superatom with superior photoluminescence obtained by ligand engineering
  Katsuya Mutoh; Teppei Yahagi; Shinjiro Takano; Sonomi Kawakita; Takeshi Iwasa; Tetsuya Taketsugu; Tatsuya Tsukuda; Takuya Nakashima
  Chemical Science, 16, 19, 8240, 8246, Royal Society of Chemistry (RSC), 28 Mar. 2025, [Peer-reviewed], [International Magazine]
  English, Scientific journal, A nearly perfect icosahedral Ir@Au₁₂ superatom was formed using a diphosphine ligand with benzo[b]phosphindole rings. The Ir@Au₁₂ superatom exhibited bright photoluminescence due to the symmetric structure with the rigidified core.
• Fragmentation-Based Linear-Scaling Method for Strongly Correlated Systems: Divide-and-Conquer Hartree–Fock–Bogoliubov Method, Its Energy Gradient, and Applications to Graphene Nano-Ribbon Systems
  Masato Kobayashi; Ryosuke Kodama; Tomoko Akama; Tetsuya Taketsugu
  Chemistry, 7, 2, 46, MDPI AG, 18 Mar. 2025, [Peer-reviewed], [Invited], [Last author], [International Magazine]
  English, Scientific journal, This study introduces a fragmentation-based linear-scaling method for strongly correlated systems, specifically the divide-and-conquer Hartree–Fock–Bogoliubov (DC-HFB) approach. Two energy gradient formulations of the DC-HFB method are derived and implemented, enabling efficient optimization of molecular geometries in large systems. This method is applied to graphene nanoribbons (GNRs) to explore their geometries and polyradical characters. Numerical results demonstrate that the present DC-HFB method has the potential to treat the static electron correlation and predict diradical character in GNRs, offering new avenues for studying large-scale strongly correlated systems.
• Revealing the electron driven mechanism in metal catalyzed Kumada cross coupling reaction
  Noriyuki Takai; Takuro Tsutsumi; Kenichiro Saita; Tetsuya Taketsugu; Takao Tsuneda
  Scientific Reports, 15, 1, 4421, Springer Science and Business Media LLC, 05 Feb. 2025, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Theoretical design of nanocatalysts based on (Fe2O3)n clusters for hydrogen production from ammonia
  Sapajan Ibragimov; Andrey Lyalin; Sonu Kumar; Yuriko Ono; Tetsuya Taketsugu; Maciej Bobrowski
  The Journal of Chemical Physics, 162, 5, AIP Publishing, 04 Feb. 2025, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal, The catalytic activities of high-spin small Fe(III) oxides have been investigated for efficient hydrogen production through ammonia decomposition, using the artificial force induced reaction method within the framework of density functional theory with the B3LYP hybrid exchange–correlation functional. Our results reveal that the adsorption free energy of NH3 on (Fe2O3)n (n = 1–4) decreases with increasing cluster size up to n = 3, followed by a slight increase at n = 4. The strongest NH3 adsorption energy, 28.55 kcal/mol, was found for Fe2O3, where NH3 interacts with a two-coordinated Fe site, forming an Fe–N bond with a length of 2.11 Å. A comparative analysis of NH3 dehydrogenation and H2 formation on various Fe(III) oxide sizes identifies the rate-determining steps for each reaction. We found that the rate-determining step for the full NH3 dehydrogenation on (Fe2O3)n (n = 1–4) is size-dependent, with the NH* → N* + H* reaction acting as the limiting step for n = 1–3. In addition, our findings indicate that H2 formation is favored following the partial decomposition of NH3 on Fe(III) oxides.
• Charge transfer emission between π- and 4f-orbitals in a trivalent europium complex
  Yuichi Kitagawa; Toranosuke Tomikawa; Kota Aikawa; Shiori Miyazaki; Tomoko Akama; Masato Kobayashi; Mengfei Wang; Sunao Shoji; Koji Fushimi; Kiyoshi Miyata; Yuichi Hirai; Takayuki Nakanishi; Ken Onda; Tetsuya Taketsugu; Yasuchika Hasegawa
  Communications Chemistry, 8, 1, 24, Springer Science and Business Media LLC, 28 Jan. 2025, [Peer-reviewed], [International Magazine]
  Scientific journal
• Boron-induced transformation of ultrathin Au films into two-dimensional metallic nanostructures
  Alexei Preobrajenski; Nikolay Vinogradov; David A. Duncan; Tien-Lin Lee; Mikhail Tsitsvero; Tetsuya Taketsugu; Andrey Lyalin
  Nature Communications, 15, 1, 10518, Springer Science and Business Media LLC, 10 Dec. 2024, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal, Abstract
  
  The synthesis of large, freestanding, single-atom-thick two-dimensional (2D) metallic materials remains challenging due to the isotropic nature of metallic bonding. Here, we present a bottom-up approach for fabricating macroscopically large, nearly freestanding 2D gold (Au) monolayers, consisting of nanostructured patches. By forming Au monolayers on an Ir(111) substrate and embedding boron (B) atoms at the Au/Ir interface, we achieve suspended monoatomic Au sheets with hexagonal structures and triangular nanoscale patterns. Alternative patterns of periodic nanodots are observed in Au bilayers on the B/Ir(111) substrate. Using scanning tunneling microscopy, X-ray spectroscopies, and theoretical calculations, we reveal the role of buried B species in forming the nanostructured Au layers. Changes in the Au monolayer’s band structure upon substrate decoupling indicate a transition from 3D to 2D metal bonding. The resulting Au films exhibit remarkable thermal stability, making them practical for studying the catalytic activity of 2D gold.
• Acceleration of Reaction Space Projector Analysis Using Combinatorial Optimization: Application to Organic Chemical Reactions
  Lihao Qu; Takuro Tsutsumi; Yuriko Ono; Tetsuya Taketsugu
  Journal of Chemical Theory and Computation, 20, 10931, 10941, American Chemical Society (ACS), 09 Dec. 2024, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Low-dimensional projection of reactivity classes in chemical reaction dynamics using supervised dimensionality reduction.
  Ryoichi Tanaka; Yuta Mizuno; Takuro Tsutsumi; Mikito Toda; Tetsuya Taketsugu; Tamiki Komatsuzaki
  The Journal of Chemical Physics, 161, 15, 154103, 21 Oct. 2024, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Transition state theory (TST) provides a framework to estimate the rate of chemical reactions. Despite its great success with many reaction systems, the underlying assumptions such as local equilibrium and nonrecrossing do not necessarily hold in all cases. Although dynamical systems theory can provide the mathematical foundation of reaction tubes existing in phase space that enables us to predict the fate of reactions free from the assumptions of TST, numerical demonstrations for large systems have been yet one of the challenges. Here, we propose a dimensionality reduction algorithm to demonstrate structures in phase space (called reactive islands) that predict reactivity in systems with many degrees of freedom. The core of this method is the application of supervised principal component analysis, where a coordinate transformation is performed to preserve the dynamical information on reactivity (i.e., to which potential basin the system moves from a region of interest) as much as possible. The reactive island structures are expected to be reflected in the transformed, low-dimensional phase space. As an illustrative example, the algorithm is scrutinized using a modified Hénon-Heiles Hamiltonian system extended to many degrees of freedom, which has three channels leading to three different products from one stable potential basin. It is shown that our algorithm can predict the reactivity in the transformed, low-dimensional coordinate system better than a naïve coordinate system and that the reactivity distribution in the transformed low-dimensional space is considered to reflect the underlying reactive islands.
• Optical force and torque in near-field excitation of C3H6: A first-principles study using RT-TDDFT
  Risa Amano; Daisuke Nishizawa; Tetsuya Taketsugu; Takeshi Iwasa
  The Journal of Chemical Physics, 161, 12, 124110, AIP Publishing, 26 Sep. 2024, [Peer-reviewed], [International Magazine]
  Scientific journal, Optical trapping is an effective tool for manipulating micrometer-sized particles, although its application to nanometer-sized particles remains difficult. The field of optical trapping has advanced significantly, incorporating more advanced techniques such as plasmonic structures. However, single-molecule trapping remains a challenge. To achieve a deeper understanding of optical forces acting on molecular systems, a first-principles approach to analyze the optical force on molecules interacting with a plasmonic field is crucial. In our study, the optical force and torque induced by the near-field excitation of C3H6 were investigated using real-time time-dependent density functional theory calculations on real-space grids. The near field from the scanning tunneling probe was adopted as the excitation source for the molecule. The optical force was calculated using the polarization charges induced in the molecule based on Lorentz force. While the optical force and torque calculated as functions of the light energy were in moderate agreement with the oscillator strengths obtained from the far-field excitation of C3H6, a closer correspondence was achieved with the power spectrum of the induced dipole moment using near-field excitation. Time-domain analysis of the optical force suggests that the simultaneous excitation of multiple excited states generally weakens the force because of mismatches between the directions of the induced polarization and the electric field. This study revealed a subtle damping mechanism for the optical force arising from intrinsic electronic states and the influence of beating.
• Electrocatalytic Ammonia Oxidation to Nitrite and Nitrate with NiOOH‐Ni
  Hanwen Liu; Cheng‐Jie Yang; Chung‐Li Dong; Jiashu Wang; Xin Zhang; Andrey Lyalin; Tetsuya Taketsugu; Zhiqi Chen; Daqin Guan; Xiaomin Xu; Zongping Shao; Zhenguo Huang
  Advanced Energy Materials, 2401675, Wiley, 07 Aug. 2024, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal, Abstract
  
  Ammonia electrooxidation in aqueous solutions can be a highly energy‐efficient process in producing nitrate and nitrite while generating hydrogen under ambient conditions. However, the kinetics of this reaction are slow and the role of catalyst in facilitating ammonia electrooxidation is not well understood. In this study, a high‐performance NiOOH‐Ni catalyst is introduced for converting ammonia into nitrite with Faraday efficiency of up to 90.4% and nitrate production rate of 1 mg h⁻¹ cm⁻². By employing Operando techniques, the role of NiOOH catalyst is elucidated in the dynamic electrooxidation of ammonia. Density functional theory (DFT) calculations support experimental observations and reveal the mechanism of the electrochemical oxidation of ammonia to nitrite and nitrate. Overall, this research contributes to the development of a cost‐effective and highly efficient catalyst for large‐scale ammonia electrolysis, while shedding light on the underlying mechanism of the NiOOH catalyst in ammonia electrooxidation.
• Near-field induced local excitation dynamics of Na10 and Na10–N2 from real-time TDDFT
  Daisuke Nishizawa; Risa Amano; Tetsuya Taketsugu; Takeshi Iwasa
  The Journal of Chemical Physics, 161, 5, 054309, AIP Publishing, 05 Aug. 2024, [Peer-reviewed], [International Magazine]
  Scientific journal, Electron dynamics of the Na10 chain and the Na10–N2 complex locally excited by an atomistic optical near-field are investigated using real-time time-dependent density functional theory calculations on real-space grids. Ultrafast laser pulses were used to simulate the near-field excitation under on- and off-resonance conditions. Off-resonance excitation did not lead to the propagation of the excitation through the Na10 chain. In contrast, under the resonance conditions, the excited state is delocalized over the entire Na chain. Analysis of the local dipole moment of each atom in Na10 indicates that this behavior is consistent with the transition density. Adding an N2 molecule to the opposite end of the local excitation region results in energy transfer via the Na10 chain. The energy transfer efficiency of the N2 molecule is well correlated with the absorption spectrum of Na10. The present study paves the way for realizing remote excitation and photonic devices at the atomic scale.
• Piperazine based pH-responsive cyanine dyes for cancer cell photoacoustic imaging
  Koki Tsuchiya; Hideo Takakura; Kohei Nakajima; Naoya Ieda; Takashi Kaneko; Takeshi Hirasawa; Masato Kobayashi; Yoshihisa Yamaoka; Miya Ishihara; Tetsuya Taketsugu; Mikako Ogawa
  Journal of Photochemistry and Photobiology A: Chemistry, 453, 115634, 115634, Elsevier BV, Aug. 2024, [Peer-reviewed], [International Magazine]
  Scientific journal
• Molecular Dynamics‐Based Conformational Simulation Method for Analysis of Arrival Time Distributions in Ion Mobility Mass Spectrometry
  Keisuke Tashiro; Yuki Ide; Tetsuya Taketsugu; Kazuaki Ohara; Kentaro Yamaguchi; Masato Kobayashi; Yasuhide Inokuma
  Advanced Theory and Simulations, 2400691, Wiley, 27 Jul. 2024, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Abstract
  
  Ion mobility‐mass spectrometry (IM‐MS) has recently contributed to the structural analysis of molecules, including supramolecules and proteins, by determining the ion arrival time distributions correlated with the collision cross sections (CCSs), as well as the mass‐to‐charge ratios. However, its application range is still limited owing to the lack of general CCSs simulation methods based on possible molecular conformations. Here, a molecular dynamics‐based conformational search method for simulating CCS distributions using projection approximation is reported. As a case study, the gas‐phase conformations of the sodium adducts of conformationally flexible polyketones with 3,3‐dimethylpentane‐2,4‐dione as the monomer are analyzed. The sodium adduct of the hexamer (m/z 781.4 for [1 + Na]⁺) showed a monomodal arrival time distribution, but that of the octamer sodium adduct (m/z 1033.5 for [2 + Na]⁺) is multimodal. The conformational analysis indicated an unimodal CCS distribution of simulated [1 + Na]⁺ conformations in which the sodium cation is mainly bound at the chain terminal. Conversely, four clusters of conformations are obtained for [2 + Na]⁺ based on the Na⁺‐coordination sites, which qualitatively reproduced the observed CCS distribution. This approach will extend the utility of IM‐MS for the conformational analysis of flexible molecules in the gas phase.
• Unveiling the Nature of Chemical Bonds in Real Space
  Takeshi Hara; Masatoshi Hasebe; Takao Tsuneda; Toshio Naito; Yuiga Nakamura; Naoyuki Katayama; Tetsuya Taketsugu; Hiroshi Sawa
  Journal of the American Chemical Society, 146, 23825, 23830, American Chemical Society (ACS), 17 Jul. 2024, [Peer-reviewed], [International Magazine]
  Scientific journal
• Singlet Fission as the Gateway to Triplet Generation in Heavy Atom-Free Organic Molecules
  Takao Tsuneda; Tetsuya Taketsugu
  The Journal of Physical Chemistry Letters, 15, 6676, 6684, American Chemical Society (ACS), 20 Jun. 2024, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal
• Novel Descriptor of Potential Energy Surface: Persistent Homology of Reaction Route Map
  Burai MURAYAMA; Masato KOBAYASHI; Masamitsu AOKI; Suguru ISHIBASHI; Takuya SAITO; Takenobu NAKAMURA; Hiroshi TERAMOTO; Tetsuya TAKETSUGU
  Journal of Computer Chemistry, Japan, 23, 1, 33, 36, Society of Computer Chemistry Japan, Jun. 2024, [Peer-reviewed], [Invited], [Last author], [Domestic magazines]
  Japanese, Scientific journal
• Chiral Tetrakis Eu(III) Complexes with Ammonium Cations for Improved Circularly Polarized Luminescence.
  Makoto Tsurui; Ryohei Takizawa; Yuichi Kitagawa; Mengfei Wang; Masato Kobayashi; Tetsuya Taketsugu; Yasuchika Hasegawa
  Angewandte Chemie (International ed. in English), e202405584, 26 May 2024, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Large dissymmetry factor of the circularly polarized luminescence (gCPL) was observed in ligand and coordination tuned chiral tetrakis europium (Eu(III)) complexes with ammonium cations. The gCPL value was estimated to be -1.54, which is the largest among chiral luminescent molecules. Through photophysical measurements, single crystal X-ray structural analyses and quantum chemical calculations, changes in the geometric and electronic structures were observed for a series of chiral tetrakis Eu(III) complexes which enhanced the gCPL value. The emission quantum yield and photosensitized energy transfer efficiencies of chiral Eu(III) complexes with ammonium cations were also larger than that with previous Cs+. Based on the systematic modifications and analyses for chiral tetrakis Eu(III) complex, effect of the ammonium cation on enhanced CPL brightness is reported.
• Development of Complete Enumeration Program for Polymer Structural Isomers: A Case of Nylon-n (n = 3-10)
  Gikyo Usuki; Takuro Tsutsumi; Kohei Hasebe; Masato Kobayashi; Keitaro Matsuoka; Tetsuya Taketsugu; Kazuki Sada
  American Chemical Society (ACS), 24 May 2024
  The enumeration of structural isomers of organic molecules using programs capable of enumerating all structural isomers for a given molecular formula has been expanding the chemical library. Here, we report the development of the program (PolyENU) that completely enumerates polymer structural isomers. PolyENU program enumerates all isomers of the repeating unit defined by a molecular formula and a functional group constituting the polymer structure. From the repeating unit of nylon 6 (C6H11NO and an amide group), 387 polymer isomers were generated by PolyENU. The enumerated polymer library includes common organic polymers such as nylon 6, polyleucine, poly(2-isopropyl-oxazoline), and poly(N-propylacrylamide), as well as many unexplored polymers. The enumeration of nylon n (n = 3-10) yielded 36,505 polymers within 44 minutes. These results clearly indicate that PolyENU expands polymer chemical space and contributes to diversity in polymer science.
• Guest-Responsive Near-Infrared-Luminescent Metal–Organic Cage Organized by Porphyrin Dyes and Yb(III) Complexes
  Shota Hosoya; Sunao Shoji; Takayuki Nakanishi; Masato Kobayashi; Mengfei Wang; Koji Fushimi; Tetsuya Taketsugu; Yuichi Kitagawa; Yasuchika Hasegawa
  Inorganic Chemistry, 63, 10108, 10113, American Chemical Society (ACS), 21 May 2024, [Peer-reviewed], [International Magazine]
  Scientific journal
• An encompassed representation of timescale hierarchies in first-order reaction network
  Yutaka Nagahata; Masato Kobayashi; Mikito Toda; Satoshi Maeda; Tetsuya Taketsugu; Tamiki Komatsuzaki
  Proceedings of the National Academy of Sciences, 121, 21, e2317781121, Proceedings of the National Academy of Sciences, 17 May 2024, [Peer-reviewed], [International Magazine]
  Scientific journal, Complex networks are pervasive in various fields such as chemistry, biology, and sociology. In chemistry, first-order reaction networks are represented by a set of first-order differential equations, which can be constructed from the underlying energy landscape. However, as the number of nodes increases, it becomes more challenging to understand complex kinetics across different timescales. Hence, how to construct an interpretable, coarse-graining scheme that preserves the underlying timescales of overall reactions is of crucial importance. Here, we develop a scheme to capture the underlying hierarchical subsets of nodes, and a series of coarse-grained (reduced-dimensional) rate equations between the subsets as a function of time resolution from the original reaction network. Each of the coarse-grained representations guarantees to preserve the underlying slow characteristic timescales in the original network. The crux is the construction of a lumping scheme incorporating a similarity measure in deciphering the underlying timescale hierarchy, which does not rely on the assumption of equilibrium. As an illustrative example, we apply the scheme to four-state Markovian models and Claisen rearrangement of allyl vinyl ether (AVE), and demonstrate that the reduced-dimensional representation accurately reproduces not only the slowest but also the faster timescales of overall reactions although other reduction schemes based on equilibrium assumption well reproduce the slowest timescale but fail to reproduce the second-to-fourth slowest timescales with the same accuracy. Our scheme can be applied not only to the reaction networks but also to networks in other fields, which helps us encompass their hierarchical structures of the complex kinetics over timescales.
• Advanced theoretical design of light-driven molecular rotary motors: enhancing thermal helix inversion and visible-light activation
  Weiliang Shi; Jianzheng Ma; Chenwei Jiang; Tetsuya Taketsugu
  Physical Chemistry Chemical Physics, 26, 21, 15672, 15680, Royal Society of Chemistry (RSC), May 2024, [Peer-reviewed], [Last author, Corresponding author], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal, We have introduced a new light-driven molecular rotary motor, achieving two crucial advancements: reducing the thermal helix inversion barrier and extending the absorption wavelength into the visible spectrum.
• Development of a red-shifted photosensitizer for near-infrared photoimmunotherapy of cancer
  Yuto Goto; Kanta Ando; Hideo Takakura; Kohei Nakajima; Masato Kobayashi; Osamu Inanami; Tetsuya Taketsugu; Mikako Ogawa
  Journal of Photochemistry and Photobiology, 20, 100230, 100230, Elsevier BV, Apr. 2024, [Peer-reviewed], [International Magazine]
  Scientific journal
• Defect passivation in methylammonium/bromine free inverted perovskite solar cells using charge-modulated molecular bonding
  Dhruba B. Khadka; Yasuhiro Shirai; Masatoshi Yanagida; Hitoshi Ota; Andrey Lyalin; Tetsuya Taketsugu; Kenjiro Miyano
  Nature Communications, 15, 882, 29 Jan. 2024, [Peer-reviewed], [International Magazine]
  Scientific journal
• Theoretical Design and Synthesis of Caged Compounds Using X‐Ray‐Triggered Azo Bond Cleavage
  Koki Ogawara; Osamu Inanami; Hideo Takakura; Kenichiro Saita; Kohei Nakajima; Sonu Kumar; Naoya Ieda; Masato Kobayashi; Tetsuya Taketsugu; Mikako Ogawa
  Advanced Science, 2306586, Wiley, 15 Jan. 2024, [Peer-reviewed], [International Magazine]
  Scientific journal, Abstract
  
  Caged compounds are frequently used in life science research. However, the light used to activate them is commonly absorbed and scattered by biological materials, limiting their use to basic research in cells or small animals. In contrast, hard X‐rays exhibit high bio‐permeability due to the difficulty of interacting with biological molecules. With the main goal of developing X‐ray activatable caged compounds, azo compounds are designed and synthesized with a positive charge and long π‐conjugated system to increase the reaction efficiency with hydrated electrons. The azo bonds in the designed compounds are selectively cleaved by X‐ray, and the fluorescent substance Diethyl Rhodamine is released. Based on the results of experiments and quantum chemical calculations, azo bond cleavage is assumed to occur via a two‐step process: a two‐electron reduction of the azo bond followed by N─N bond cleavage. Cellular experiments also demonstrate that the azo bonds can be cleaved intracellularly. Thus, caged compounds that can be activated by an azo bond cleavage reaction promoted by X‐ray are successfully generated.
• Singlet fission initiating organic photosensitizations
  Takao Tsuneda; Tetsuya Taketsugu
  Scientific Reports, 14, 1, Springer Science and Business Media LLC, 08 Jan. 2024, [Peer-reviewed], [Last author], [International Magazine]
  English, Scientific journal, Abstract
  
  The feasibility of singlet fission (SF) in organic photosensitizers is investigated through spin-flip long-range corrected time-dependent density functional theory. This study focuses on four major organic photosensitizer molecules: benzophenone, boron-dipyrromethene, methylene blue, and rose bengal. Calculations demonstrate that all these molecules possess moderate $$\pi$$-stacking energies and closely-lying singlet (S) and quintet (triplet–triplet, TT) excitations, satisfying the essential conditions for SF: (1) Near-degenerate low-lying S and (TT) excitations with a significant S–T energy gap, and (2) Moderate $$\pi$$-stacking energy of chromophores, slightly higher than solvation energy, enabling dissociation for triplet-state chromophore generation. Moreover, based on the El-Sayed rule, intersystem crossing is found to simultaneously proceed at very slow rates in all these photosensitizers. This is attributed to the fact that the lowest singlet excitation of the monomers partly involves $$n\pi ^*$$ transitions alongside the main $$\pi \pi ^*$$ transitions. The proposed mechanisms are strongly substantiated by comparisons with experimental studies.
• Ultrafast Raman observation of the perpendicular intermediate phantom state of stilbene photoisomerization
  Hikaru Kuramochi; Takuro Tsutsumi; Kenichiro Saita; Zhengrong Wei; Masahisa Osawa; Pardeep Kumar; Li Liu; Satoshi Takeuchi; Tetsuya Taketsugu; Tahei Tahara
  Nature Chemistry, 16, 1, 22, 27, Springer Science and Business Media LLC, 05 Jan. 2024, [Peer-reviewed], [International Magazine]
  Scientific journal
• A Steric-Repulsion-Driven Clutch Stack of Triaryltriazines: Correlated Molecular Rotations and a Thermoresponsive Gearshift in the Crystalline Solid
  Mingoo Jin; Ryunosuke Kitsu; Natsumi Hammyo; Ayana Sato-Tomita; Motohiro Mizuno; Alexander S. Mikherdov; Mikhail Tsitsvero; Andrey Lyalin; Tetsuya Taketsugu; Hajime Ito
  Journal of the American Chemical Society, 145, 27512, 275220, American Chemical Society (ACS), 07 Dec. 2023, [Peer-reviewed], [International Magazine]
  Scientific journal
• On-Surface Synthesis of Multiple Cu Atom-Bridged Organometallic Oligomers
  Kewei Sun; Kazuma Sugawara; Andrey Lyalin; Yusuke Ishigaki; Kohei Uosaki; Oscar Custance; Tetsuya Taketsugu; Takanori Suzuki; Shigeki Kawai
  ACS Nano, 17, 24355, 24362, American Chemical Society (ACS), 04 Dec. 2023, [Peer-reviewed], [International Magazine]
  Scientific journal
• Roles of Singlet Fission in the Photosensitization of Silicon Phthalocyanine
  Takao Tsuneda; Tetsuya Taketsugu
  Journal of Physical Chemistry Letters, 14, 11587, 11596, American Chemical Society, Dec. 2023, [Peer-reviewed], [Last author], [International Magazine]
  English, Scientific journal, The roles of singlet fission in the triplet generation of silicon phthalocyanine (SiPc), a compound analogous to the IRDye700DX photosensitizer used in near-infrared photoimmunotherapy, are investigated by considering the energetical relation between the
  excitations of this compound. These excitations are obtained through spin−flip long-range corrected time-dependent density functional theory calculations. To initiate singlet fission, chromophores must meet two conditions: (1) near-degenerate low-lying singlet and quintet (triplet−triplet) excitations with a considerable energy gap of the lowest singlet and triplet excited states and (2) moderate π-stacking energy of chromophores, which is higher than but
  not far from the solvation energy, to facilitate the dissociation and generation of triplet-state chromophores. The present calculations demonstrate that SiPc satisfies both of these conditions after the formation of π-stacking irrespective of the presence of an axial ligand(s), suggesting that singlet fission plays a crucial role in the triplet generation process, although intersystem crossing occurs simultaneously at a very slow rate.
• Ab initio molecular dynamics study of intersystem crossing dynamics for MH2 (M = Si, Ge, Sn, Pb) on spin‐pure and spin‐mixed potential energy surfaces
  Satoi Wada; Takuro Tsutsumi; Kenichiro Saita; Tetsuya Taketsugu
  Journal of Computational Chemistry, 45, 552, 562, Wiley, 27 Nov. 2023, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal, Abstract
  
  Recently, surface‐hopping ab initio molecular dynamics (SH‐AIMD) simulations have come to be used to discuss the mechanisms and dynamics of excited‐state chemical reactions, including internal conversion and intersystem crossing. In dynamics simulations involving intersystem crossing, there are two potential energy surfaces (PESs) governing the motion of nuclei: PES in a spin‐pure state and PES in a spin‐mixed state. The former gives wrong results for molecular systems with large spin‐orbit coupling (SOC), while the latter requires a potential gradient that includes a change in SOC at each point, making the computational cost very high. In this study, we systematically investigate the extent to which the magnitude of SOC affects the results of the spin‐pure state‐based dynamics simulations for the hydride MH₂ (M = Si, Ge, Sn, Pb) by performing SH‐AIMD simulations based on spin‐pure and spin‐mixed states. It is clearly shown that spin‐mixed state PESs are indispensable for the dynamics simulation of intersystem crossing in systems containing elements Sn and Pb from the fifth period onward. Furthermore, in addition to the widely used Tully's fewest switches (TFS) algorithm, the Zhu‐Nakamura (ZN) global switching algorithm, which is computationally less expensive, is applied to SH for comparison. The results from TFS‐ and ZN‐SH‐AIMD methods are in qualitative agreement, suggesting that the less expensive ZN‐SH‐AIMD can be successfully utilized to investigate the dynamics of photochemical reactions based on quantum chemical calculations.
• Total and orbital density‐based analyses of molecules revealing long‐range interaction regions
  Masatoshi Hasebe; Takuro Tsutsumi; Tetsuya Taketsugu; Takao Tsuneda
  Journal of Computational Chemistry, 44, 2391, 2403, Wiley, 05 Sep. 2023, [Peer-reviewed], [International Magazine]
  Scientific journal, Abstract
  
  Total and orbital electron densities of molecules are explored for the effect of the long‐range correction (LC) for density functional theory (DFT) exchange functionals by comparing to the effect of the ab initio coupled cluster singles and doubles (CCSD) method. Calculating the LC effect on the total electron densities shows that the LC stabilizes the electrons around the long‐range interaction regions of kinetic energy density, which are assumed to be electrons other than free electrons and self‐interacting electrons, while the CCSD method stabilizes the electrons in the long‐range interaction regions in the vertical molecular planes. As a more precise test, the LC effect on orbital densities are compared to the CCSD effect on Dyson orbital densities. Surprisingly, these effects are similar for the unoccupied orbitals, indicating that the LC covers the effects required to reproduce the CCSD Dyson unoccupied orbitals. For exploring the discrepancies between these effects on the occupied orbitals, the photoionization cross sections are calculated as a direct test for the shapes of the HOMOs to investigate the differences between these effects on the occupied orbitals. Consequently, the LC clearly produces the canonical HOMOs close to the CCSD Dyson and experimental ones, except for the HOMO of benzene molecule that mixes with the HOMO1 for the CCSD Dyson orbitals. This indicates that the orbital analyses using the photoionization cross sections are available as a direct test for the quality of DFT functionals.
• Reproducing the Reaction Route Map on the Shape Space from Its Quotient by the Complete Nuclear Permutation-Inversion Group
  Hiroshi Teramoto; Takuya Saito; Masamitsu Aoki; Burai Murayama; Masato Kobayashi; Takenobu Nakamura; Tetsuya Taketsugu
  Journal of Chemical Theory and Computation, 19, 17, 5886, 5896, American Chemical Society (ACS), 29 Aug. 2023, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal
• Dimetal‐Binding Scaffold 2‐(Pyridin‐2‐yl)imidazo [1,5‐b]pyridazine‐7‐ylidene: Synthesis of Trinuclear Heterobimetallic Complexes Involving Gold‐Metal Interactions
  Akito Kitabayashi; Yuriko Ono; Tetsuya Taketsugu; Masaya Sawamura; Kosuke Higashida
  Chemistry – A European Journal, 29, e202301673, Wiley, 09 Aug. 2023, [Peer-reviewed], [International Magazine]
  Scientific journal, Abstract
  
  As a dimetal‐binding rigid scaffold, 2‐(pyridin‐2‐yl)imidazo[1,5‐b]pyridazine‐7‐ylidene was introduced. The scaffold was first converted into a meridional Au,N,N‐tridentate ligand through binding of a Au(I)Cl moiety at the carbene center. The Au(I) center and the N,N‐chelating moiety were expected to function as metallophilic and 4e‐σ‐donative interaction sites, respectively, in the binding of the second metal center. In this manner, various trinuclear heterobimetallic complexes were synthesized with different 3d‐metal sources, such as cationic Cu^I, Cu^II, Ni^II, and Co^II salts. SC‐XRD analysis showed that the mono‐3d‐metal di‐gold(I) trinuclear heterobimetallic complexes were constructed through gold(I)‐metal interactions. Metallophilic interactions were also investigated by quantum chemical calculations including the AIM and IGMH methods.
• Designing main-group catalysts for low-temperature methane combustion by ozone
  Shunsaku Yasumura; Kenichiro Saita; Takumi Miyakage; Ken Nagai; Kenichi Kon; Takashi Toyao; Zen Maeno; Tetsuya Taketsugu; Ken-ichi Shimizu
  Nature Communications, 14, 1, 3926, Springer Science and Business Media LLC, 03 Jul. 2023, [Peer-reviewed], [International Magazine]
  Scientific journal, Abstract
  
  The catalytic combustion of methane at a low temperature is becoming increasingly key to controlling unburned CH₄ emissions from natural gas vehicles and power plants, although the low activity of benchmark platinum-group-metal catalysts hinders its broad application. Based on automated reaction route mapping, we explore main-group elements catalysts containing Si and Al for low-temperature CH₄ combustion with ozone. Computational screening of the active site predicts that strong Brønsted acid sites are promising for methane combustion. We experimentally demonstrate that catalysts containing strong Bronsted acid sites exhibit improved CH₄ conversion at 250 °C, correlating with the theoretical predictions. The main-group catalyst (proton-type beta zeolite) delivered a reaction rate that is 442 times higher than that of a benchmark catalyst (5 wt% Pd-loaded Al₂O₃) at 190 °C and exhibits higher tolerance to steam and SO₂. Our strategy demonstrates the rational design of earth-abundant catalysts based on automated reaction route mapping.
• Characterizing Reaction Route Map of Realistic Molecular Reactions Based on Weight Rank Clique Filtration of Persistent Homology
  Burai Murayama; Masato Kobayashi; Masamitsu Aoki; Suguru Ishibashi; Takuya Saito; Takenobu Nakamura; Hiroshi Teramoto; Tetsuya Taketsugu
  Journal of Chemical Theory and Computation, 19, 15, 5007, 5023, American Chemical Society (ACS), 03 Jul. 2023, [Peer-reviewed], [Last author], [International Magazine]
  English, Scientific journal
• Ab initio calculations on structure and stability of BN/CC isosterism in azulene
  Mohamed A. Abdel-Rahman; Kamal A. Soliman; Safwat Abdel-Azeim; Ahmed M. El-Nahas; Tetsuya Taketsugu; Takahito Nakajima; Asmaa B. El-Meligy
  Scientific Reports, 13, 1, 10260, Springer Science and Business Media LLC, 24 Jun. 2023, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal, Abstract
  
  Herein, we investigated the thermodynamic stability and opto-electronic properties of a newly BN-doped azulene. The gas-phase formation enthalpies of 11 BN-doped azulene were calculated by the atomization energy method using three computational models (CBS-APNO, CBS-QB3, and G3MP2). The results suggest that AZ-1N9B exhibits the highest stability among the studied isomers. On the other hand, AZ-1B9N and AZ-9B10N display nearly equal stability with relative energies of 19.36 and 19.82 kcal/mol at CBS-QB3, respectively. These two isomers are considered the least stable among the investigated compounds. The frontier molecular orbitals (FMO), ionization energies (IE), and electron affinities (EA) of these isomers were discussed. Additionally, the electronic absorption spectra of the BN-doped azulenes were computed using the TD-B3LYP/6–31 + G(d,p) and TD-CAM-B3LYP level of theories, which using a long-range corrected hybrid functional in acetone. The computational results obtained in this research are align closely with the existing literature, thereby reinforcing the credibility and reliability of our findings.
• Computational survey of humin formation from 5-(hydroxymethyl)furfural under basic conditions
  Keisuke Tashiro; Masato Kobayashi; Kiyotaka Nakajima; Tetsuya Taketsugu
  RSC Advances, 13, 24, 16293, 16299, Royal Society of Chemistry (RSC), 31 May 2023, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal, By repeatedly utilizing the MC-AFIR method, a comprehensive reaction-path search for the oligomerization of HMF was conducted to clarify the mechanism of humin formation in the oxidation of HMF to FDCA.
• X線によるアゾ結合の開裂により活性化されるケージド化合物の開発
  小河原 浩輝; 高倉 栄男; 中島 孝平; 斉田 謙一郎; Kumar Sonu; 小林 正人; 武次 徹也; 稲波 修; 小川 美香子
  JSMI Report, 16, 2, 64, 64, 日本分子イメージング学会, May 2023
  Japanese
• Size dependent electrocatalytic activities of h-BN for oxygen reduction reaction to water
  Hung Cuong Dinh; Ganesan Elumalai; Hidenori Noguchi; Andrey Lyalin; Tetsuya Taketsugu; Kohei Uosaki
  The Journal of Chemical Physics, 158, 13, 134713, 134713, AIP Publishing, 07 Apr. 2023, [Peer-reviewed], [Invited], [International Magazine]
  Scientific journal, Electrocatalytic activities for the oxygen reduction reaction (ORR) of Au electrodes modified by as prepared and size selected (0.45–1.0, 0.22–0.45, and 0.1–0.22 µm) h-BN nanosheet (BNNS), which is an insulator, were examined in O₂ saturated 0.5M H₂SO₄ solution. The overpotential was reduced by all the BNNS modifications, and the smaller the size, the smaller the overpotential for ORR, i.e., the larger the ORR activity, in this size range. The overpotential was reduced by as much as ∼330 mV compared to a bare Au electrode by modifying the Au surface by the BNNS of the smallest size range (0.1–0.22 µm). The overpotential at this electrode was only 80 mV more than that at the Pt electrode. Both the rotation disk electrode experiments with Koutecky–Levich analysis and rotating ring disk electrode measurements showed that more than 80% of oxygen is reduced to water via the four-electron process at this electrode. These results strongly suggest and theoretical density functional theory calculations support that the ORR active sites are located at the edges of BNNS islands adsorbed on Au(111). The decrease in size of BNNS islands results in an effective increase in the number of the catalytically active sites and, hence, in the increase in the catalytic activity of the BNNS/Au(111) system for ORR.
• Time-dependent Hartree–Fock–Bogoliubov method for molecular systems: An alternative excited-state methodology including static electron correlation
  Masatsugu Nishida; Tomoko Akama; Masato Kobayashi; Tetsuya Taketsugu
  Chemical Physics Letters, 816, 140386, 140386, Elsevier BV, Apr. 2023, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal
• Theoretical investigation of copper clusters using the electron propagator theory
  Anjani Nandan Pandey; Tetsuya Taketsugu; Raman K Singh
  Journal of Chemical Sciences, 135, 2, Springer Science and Business Media LLC, 29 Mar. 2023, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Key factors for connecting silver-based icosahedral superatoms by vertex sharing
  Sayuri Miyajima; Sakiat Hossain; Ayaka Ikeda; Taiga Kosaka; Tokuhisa Kawawaki; Yoshiki Niihori; Takeshi Iwasa; Tetsuya Taketsugu; Yuichi Negishi
  Communications Chemistry, 6, 1, 57, Springer Science and Business Media LLC, 28 Mar. 2023, [Peer-reviewed], [International Magazine]
  Scientific journal, Abstract
  
  Metal nanoclusters composed of noble elements such as gold (Au) or silver (Ag) are regarded as superatoms. In recent years, the understanding of the materials composed of superatoms, which are often called superatomic molecules, has gradually progressed for Au-based materials. However, there is still little information on Ag-based superatomic molecules. In the present study, we synthesise two di-superatomic molecules with Ag as the main constituent element and reveal the three essential conditions for the formation and isolation of a superatomic molecule comprising two Ag_13−xM_x structures (M = Ag or other metal; x = number of M) connected by vertex sharing. The effects of the central atom and the type of bridging halogen on the electronic structure of the resulting superatomic molecule are also clarified in detail. These findings are expected to provide clear design guidelines for the creation of superatomic molecules with various properties and functions.
• Real-time observation of the Woodward–Hoffmann rule for 1,3-cyclohexadiene by femtosecond soft X-ray transient absorption
  Taro Sekikawa; Nariyuki Saito; Yutaro Kurimoto; Nobuhisa Ishii; Tomoya Mizuno; Teruto Kanai; Jiro Itatani; Kenichiro Saita; Tetsuya Taketsugu
  Physical Chemistry Chemical Physics, 25, 12, 8497, 8506, Royal Society of Chemistry (RSC), 16 Feb. 2023, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal, The stereochemistry of pericyclic reactions is explained by orbital symmetry conservation, referred to as the Woodward–Hoffmann (WH) rule.
• A novel pH-Dependent sensor for recognition of strontium ions in water: A hierarchically structured mesoporous architectonics
  I.G. Alhindawy; D.A. Tolan; E.A. Elshehy; W.A. El-Said; S.M. Abdelwahab; H.I. Mira; T. Taketsugu; V.P. Utgikar; A.M. El-Nahas; A.O. Youssef
  Talanta, 253, 124064, 124064, Elsevier BV, 01 Feb. 2023, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Singlet fission initiating triplet generations of BODIPY derivatives through π-stacking: A theoretical study
  Takao Tsuneda; Tetsuya Taketsugu
  Scientific Reports, 12, 19714, Nature Springer, 16 Nov. 2022, [Peer-reviewed], [Last author], [International Magazine]
  English, Scientific journal, Comparing the adsorption energy calculations of solvent molecules, i.e., cyclohexane, chloroform and acetonitrile molecules, to the derivatives with the π-stacking energies of these derivatives surprisingly show that the hierarchy of the solvation energies and π-stacking energies strongly correlates with the experimentally-suggested solvent dependence of the triplet-state generation of these derivatives for five and more adsorbing solvent molecules. Following this finding, the excitation spectra of these derivatives in acetonitrile solvent are explored using the proprietary spin-flip long-range corrected time-dependent density functional theory. It is, consequently, confirmed that the π-stacking activates the second lowest singlet excitation to trigger the spin-allowed transition to the singlet doubly-excited tetraradical (TT)1 state, which generates the long-lived quintet (TT)1 state causing the SF. However, it is also found that the π-stacking also get a slow intersystem crossing active around the intersections of the lowest singlet excitations with the lowest triplet T1 excitations in parallel with the SF due to the charge transfer characters of the lowest singlet excitations. These results suggest that SF initiates the triplet-state generations through near-degenerate low-lying singlet and (TT) excitations with a considerable singlet-triplet energy gap after the π-stacking of chromophores stronger than the solvation. Since these derivatives are organic photosensitizers, this study proposes that SF should be taken into consideration in developing novel heavy atom-free organic photosensitizers, which will contribute to a variety of research fields such as medical care, photobiology, energy science, and synthetic chemistry.
• Multi-state Energy Landscape for Photoreaction of Stilbene and Dimethyl-stilbene
  Takuro Tsutsumi; Yuriko Ono; Tetsuya Taketsugu
  Journal of Chemical Theory and Computation, 18, 12, 7483, 7495, American Chemical Society (ACS), 09 Nov. 2022, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal
• Reactive orbital energy theory serving a theoretical foundation for the electronic theory of organic chemistry
  Takao Tsuneda; Hiroki Sumitomo; Masatoshi Hasebe; Takuro Tsutsumi; Tetsuya Taketsugu
  Journal of Computational Chemistry, 44, 2, 93, 104, Wiley, 04 Oct. 2022, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal
• Theoretical Study of Carbon Isotope Effects in the Nonclassical Carbonyl Cation CO/[M(CO) ]+ (M = Cu, Ag, Au; n = 1-4)
  Yuriko Ono; Takuro Tsutsumi; Yu Harabuchi; Tetsuya Taketsugu; Yasuhiko Fujii
  Chemical Physics Letters, 806, 140008-1, 140008-6, Elsevier BV, Sep. 2022, [Peer-reviewed], [Invited], [Corresponding author], [International Magazine]
  Scientific journal
• Extension of natural reaction orbital approach to multiconfigurational wavefunctions
  Shuichi Ebisawa; Takuro Tsutsumi; Tetsuya Taketsugu
  The Journal of Chemical Physics, 157, 8, 084118, 084118, AIP Publishing, 28 Aug. 2022, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal, Recently, we proposed a new orbital analysis method, natural reaction orbital (NRO), which automatically extracts orbital pairs that characterize electron transfer in reaction processes by singular value decomposition of the first-order orbital response matrix to the nuclear coordinate displacements [Ebisawa et al., Phys. Chem. Chem. Phys. 24, 3532 (2022)]. NRO analysis along the intrinsic reaction coordinate (IRC) for several typical chemical reactions demonstrated that electron transfer occurs mainly in the vicinity of transition states and in regions where the energy profile along the IRC shows shoulder features, allowing the reaction mechanism to be explained in terms of electron motion. However, its application has been limited to single configuration theories such as Hartree–Fock theory and density functional theory. In this work, the concept of NRO is extended to multiconfigurational wavefunctions and formulated as the multiconfiguration NRO (MC-NRO). The MC-NRO method is applicable to various types of electronic structure theories, including multiconfigurational theory and linear response theory, and is expected to be a practical tool for extracting the essential qualitative features of a broad range of chemical reactions, including covalent bond dissociation and chemical reactions in electronically excited states. In this paper, we calculate the IRC for five basic chemical reaction processes at the level of the complete active space self-consistent field theory and discuss the phenomenon of electron transfer by performing MC-NRO analysis along each IRC. Finally, issues and future prospects of the MC-NRO method are discussed.
• Ligand release from silicon phthalocyanine dyes triggered by X-ray irradiation
  Hideo Takakura; Shino Matsuhiro; Osamu Inanami; Masato Kobayashi; Kenichiro Saita; Masaki Yamashita; Kohei Nakajima; Motofumi Suzuki; Naoki Miyamoto; Tetsuya Taketsugu; Mikako Ogawa
  Organic & biomolecular chemistry, 20, 7270, 7277, 16 Aug. 2022, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Ligand release from silicon phthalocyanine (SiPc) dyes triggered by near-infrared (NIR) light is a key photochemical reaction involving caged compounds based on SiPc. Although NIR light is relatively permeable compared with visible light, this light can be attenuated by tissue absorption and scattering; therefore, using light to induce photochemical reactions deep inside the body is difficult. Herein, because X-rays are highly permeable and can produce radicals through the radiolysis of water, we investigated whether the axial ligands of SiPcs can be cleaved using X-ray irradiation. SiPcs with different axial ligands (alkoxy, siloxy, oxycarbonyl, and phenoxy groups) were irradiated with X-rays under hypoxic conditions. We found that the axial ligands were cleaved via reactions with hydrated electrons (e-aq), not OH radicals, generated from water in response to X-ray irradiation, and SiPc with alkoxy groups exhibited the highest cleavage efficiency. A quantitative investigation revealed that X-ray-induced axial ligand cleavage proceeds via a radical chain reaction. The reaction is expected to be applicable to the molecular design of X-ray-activatable functional molecules in the future.
• Superior Multielectron‐Transferring Energy Storage by π‐d Conjugated Frameworks
  Dong Xia; Ken Sakaushi; Andrey Lyalin; Keisuke Wada; Sonu Kumar; Marco Amores; Hiroaki Maeda; Sono Sasaki; Tetsuya Taketsugu; Hiroshi Nishihara
  Small, 18, 33, 2202861, 2202861, Wiley, Aug. 2022, [Peer-reviewed], [International Magazine]
  Scientific journal
• Identifying Substrate-Dependent Chemical Bonding Nature at Molecule/Metal Interfaces Using Vibrational Sum Frequency Generation Spectroscopy and Theoretical Calculations
  Ben Wang; Mikio Ito; Min Gao; Hidenori Noguchi; Kohei Uosaki; Tetsuya Taketsugu
  The Journal of Physical Chemistry C, 126, 27, 11298, 11309, American Chemical Society (ACS), 14 Jul. 2022, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal
• Effective Photosensitization in Excited‐State Equilibrium: Brilliant Luminescence of Tb ^III Coordination Polymers Through Ancillary Ligand Modifications
  Yuichi Kitagawa; Ryoma Moriake; Tomoko Akama; Koki Saito; Kota Aikawa; Sunao Shoji; Koji Fushimi; Masato Kobayashi; Tetsuya Taketsugu; Yasuchika Hasegawa
  ChemPlusChem, e202200151-1, e202200151-6, Wiley, 13 Jul. 2022, [Peer-reviewed], [International Magazine]
  Scientific journal
• Excited States of Metal-Adsorbed Dimethyl Disulfide: A TDDFT Study with Cluster Model
  Keijiro Toda; Yoshihiro Hirose; Emiko Kazuma; Yousoo Kim; Tetsuya Taketsugu; Takeshi Iwasa
  The Journal of Physical Chemistry A, 126, 26, 4191, 4198, American Chemical Society (ACS), 07 Jul. 2022, [Peer-reviewed], [International Magazine]
  Scientific journal
• Doping‐Mediated Energy‐Level Engineering of M@Au ₁₂ Superatoms (M=Pd, Pt, Rh, Ir) for Efficient Photoluminescence and Photocatalysis
  Haru Hirai; Shinjiro Takano; Takuya Nakashima; Takeshi Iwasa; Tetsuya Taketsugu; Tatsuya Tsukuda
  Angewandte Chemie International Edition, 61, 36, e202207290-1, e202207290-8, Wiley, 17 Jun. 2022, [Peer-reviewed], [International Magazine]
  Scientific journal
• Practical electronic ground- and excited-state calculation method for lanthanide complexes based on frozen core potential approximation to 4f electrons
  Masato Kobayashi; Yuta Oba; Tomoko Akama; Tetsuya Taketsugu
  Journal of Mathematical Chemistry, 61, 2, 322, 334, Springer Science and Business Media LLC, 22 May 2022, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal
• Asymmetric Lumino-Transformer: Circularly Polarized Luminescence of Chiral Eu(III) Coordination Polymer with Phase-Transition Behavior
  Makoto Tsurui; Yuichi Kitagawa; Sunao Shoji; Hitomi Ohmagari; Miki Hasegawa; Masayuki Gon; Kazuo Tanaka; Masato Kobayashi; Tetsuya Taketsugu; Koji Fushimi; Yasuchika Hasegawa
  The Journal of Physical Chemistry B, 126, 20, 3799, 3807, American Chemical Society (ACS), May 2022, [Peer-reviewed], [International Magazine]
  Scientific journal
• Dynamically Hidden Reaction Paths in the Reaction of CF₃⁺ + CO
  Kohei Oda; Takuro Tsutsumi; Srihari Keshavamurthy; Kenji Furuya; P. B. Armentrout; Tetsuya Taketsugu
  ACS Physical Chemistry Au, 2, 5, 388, 398, American Chemical Society (ACS), 27 Apr. 2022, [Peer-reviewed], [Last author, Corresponding author], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Structures, Energetics, and Spectra of (NH) and (OH) Tautomers of 2-(2-Hydroxyphenyl)-1-azaazulene: A Density Functional Theory/Time-Dependent Density Functional Theory Study
  Asmaa B. El-Meligy; Safinaz H. El-Demerdash; Mohamed A. Abdel-Rahman; Mohamed A. M. Mahmoud; Tetsuya Taketsugu; Ahmed M. El-Nahas
  ACS Omega, 7, 16, 14222, 14238, American Chemical Society (ACS), 26 Apr. 2022, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Development of Accurate Electron Correlation Calculation Method Using Annealing Machine and Machine Learning
  Masato KOBAYASHI; Ryo YONEYAMA; Sayoko NOJO; Keisuke TASHIRO; Tetsuya TAKETSUGU
  Journal of Computer Chemistry, Japan, 21, 4, 96, 98, Society of Computer Chemistry Japan, Apr. 2022, [Peer-reviewed], [Last author], [Domestic magazines]
  Scientific journal
• Axial-ligand-cleavable silicon phthalocyanines triggered by near-infrared light toward design of photosensitizers for photoimmunotherapy
  Hideo Takakura; Shino Matsuhiro; Masato Kobayashi; Yuto Goto; Mei Harada; Tetsuya Taketsugu; Mikako Ogawa
  Journal of Photochemistry and Photobiology A: Chemistry, 426, 113749, 113749, Apr. 2022, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Reaction Space Projector (ReSPer) for Visualizing Dynamic Reaction Routes Based on Reduced-Dimension Space
  Takuro Tsutsumi; Yuriko Ono; Tetsuya Taketsugu
  Topics in Current Chemistry, 380, 3, 19, Springer Science and Business Media LLC, 10 Mar. 2022, [Peer-reviewed], [Invited], [Last author, Corresponding author], [International Magazine]
  Scientific journal
• Catalytic Oxidative Dehydrogenation of Light Alkanes over Oxygen Functionalized Hexagonal Boron Nitride
  Sonu Kumar; Andrey Lyalin; Zhenguo Huang; Tetsuya Taketsugu
  ChemistrySelect, 7, 1, e202103795-1, e202103795-9, Wiley, 11 Jan. 2022, [Peer-reviewed], [Last author, Corresponding author], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Direct Confirmation of the Woodward-Hoffmann Rule by Femtosecond Transient Soft X-ray Absorption
  T. Sekikawa; N. Saito; Y. Kurimoto; N. Ishii; T. Mizuno; T. Kanai; J. Itatani; K. Saita; T. Taketsugu
  The International Conference on Ultrafast Phenomena (UP) 2022, Optica Publishing Group, 2022
  International conference proceedings, The chemical shifts of the carbon K-edge during the ring-opening dynamics of 1,3-cyclohexadiene observed by femtosecond transient soft X-ray absorption confirm that the stereochemistry of the ring-opening reaction follows the Woodward-Hoffmann rule.
• Cubically cage-shaped mesoporous ordered silica for simultaneous visual detection and removal of uranium ions from contaminated seawater
  Dina A. Tolan; Emad A. Elshehy; Waleed A. El-Said; Tetsuya Taketsugu; Kazunari Yoshizawa; Ahmed M. El-Nahas; Ali Reza Kamali; Amr M. Abdelkader
  Microchimica Acta, 189, 1, Springer Science and Business Media LLC, Jan. 2022, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Hydration, Prediction of the pKa, and Infrared Spectroscopic Study of Sulfonated Polybenzophenone (SPK) Block-Copolymer Hydrocarbon Membranes and Comparisons with Nafion
  Soni Singh; Tetsuya Taketsugu; Raman K. Singh
  ACS Omega, 6, 48, 32739, 32748, American Chemical Society (ACS), 07 Dec. 2021, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Reply to the ‘Comment on “Theoretical investigations on hydrogen peroxide decomposition in aquo”’ by W. H. Koppenol, Phys. Chem. Chem. Phys., 2021, 23, DOI: 10.1039/D1CP03545B
  Takao Tsuneda; Tetsuya Taketsugu
  Physical Chemistry Chemical Physics, 23, 45, 26006, 26008, Royal Society of Chemistry (RSC), 10 Nov. 2021, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal, The H₂O₂ decomposition reaction mechanism based on the production of a de facto Fe⁺ ion hydration complex is strongly supported by a simple test based on the Gibbs energies considering the O–O bond dissociation of H₂O₂.
• One-to-One Correspondence between Reaction Pathways and Reactive Orbitals
  Masatoshi Hasebe; Takuro Tsutsumi; Tetsuya Taketsugu; Takao Tsuneda
  Journal of Chemical Theory and Computation, 17, 11, 6901, 6909, American Chemical Society (ACS), 09 Nov. 2021, [Peer-reviewed], [International Magazine]
  Scientific journal
• Natural reaction orbitals for characterizing electron transfer responsive to nuclear coordinate displacement
  Shuichi Ebisawa; Masatoshi Hasebe; Takuro Tsutsumi; Takao Tsuneda; Tetsuya Taketsugu
  Physical Chemistry Chemical Physics, 24, 6, 3532, 3545, Royal Society of Chemistry (RSC), 03 Nov. 2021, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal, Natural reaction orbital (NRO) is proposed as a new concept for analyzing chemical reactions from the viewpoint of the electronic theory. The pair of the occupied and virtual NROs that...
• Visualization of reaction route map and dynamical trajectory in reduced dimension
  Takuro Tsutsumi; Yuriko Ono; Tetsuya Taketsugu
  Chemical Communications, 57, 89, 11734, 11750, Royal Society of Chemistry (RSC), Nov. 2021, [Last author, Corresponding author], [International Magazine]
  Scientific journal, We review the on-the-fly trajectory mapping and Reaction Space Projector methods to analyze dynamical trajectories based on a reduced-dimensionality subspace.
• Structural Characterization of Nickel-Doped Aluminum Oxide Cations by Cryogenic Ion Trap Vibrational Spectroscopy
  Ya-Ke Li; Mark C. Babin; Sreekanta Debnath; Takeshi Iwasa; Sonu Kumar; Tetsuya Taketsugu; Knut R. Asmis; Andrey Lyalin; Daniel M. Neumark
  The Journal of Physical Chemistry A, 125, 43, 9527, 9535, American Chemical Society (ACS), 24 Oct. 2021, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Barium Oxide Encapsulating Cobalt Nanoparticles Supported on Magnesium Oxide: Active Non-Noble Metal Catalysts for Ammonia Synthesis under Mild Reaction Conditions
  Katsutoshi Sato; Shin-ichiro Miyahara; Kotoko Tsujimaru; Yuichiro Wada; Takaaki Toriyama; Tomokazu Yamamoto; Syo Matsumura; Koji Inazu; Hirono Mohri; Takeshi Iwasa; Tetsuya Taketsugu; Katsutoshi Nagaoka
  ACS Catalysis, 11, 21, 13050, 13061, American Chemical Society (ACS), 13 Oct. 2021, [Peer-reviewed], [International Magazine]
  Scientific journal
• Honeycomb Boron on Al(111): From the Concept of Borophene to the Two-Dimensional Boride
  Alexei B. Preobrajenski; Andrey Lyalin; Tetsuya Taketsugu; Nikolay A. Vinogradov; Alexander S. Vinogradov
  ACS Nano, 15, 9, 15153, 15165, American Chemical Society (ACS), 28 Sep. 2021, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Switching the relaxation pathway by steric effects in conjugated dienes
  Tateharu Tentaku; Ryunosuke Atobe; Takuro Tsutsumi; Sota Satoh; Yu Harabuchi; Tetsuya Taketsugu; Taro Sekikawa
  Journal of Physics B: Atomic, Molecular and Optical Physics, 54, 174004, IOP Publishing, 16 Sep. 2021, [Peer-reviewed], [Invited], [International Magazine]
  Scientific journal
• Catalytic Functionalization of Hexagonal Boron Nitride for Oxidation and Epoxidation Reactions by Molecular Oxygen
  Min Gao; Ben Wang; Takao Tsuneda; Andrey Lyalin; Tetsuya Taketsugu
  The Journal of Physical Chemistry C, 125, 35, 19219, 19228, American Chemical Society (ACS), 09 Sep. 2021, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• A comparative study of structural, electronic, and optical properties of thiolated gold clusters with icosahedral vs face-centered cubic cores
  Maho Miyamoto; Tetsuya Taketsugu; Takeshi Iwasa
  The Journal of Chemical Physics, 155, 9, 094304, 094304, AIP Publishing, 07 Sep. 2021, [Peer-reviewed], [Invited], [International Magazine]
  English, Scientific journal
• Mechanism of 2,6-Dichloro-4,4′-bipyridine-Catalyzed Diboration of Pyrazines Involving a Bipyridine-Stabilized Boryl Radical
  Toshimichi Ohmura; Yohei Morimasa; Tomoya Ichino; Yusuke Miyake; Yasujiro Murata; Michinori Suginome; Kunihiko Tajima; Tetsuya Taketsugu; Satoshi Maeda
  Bulletin of the Chemical Society of Japan, 94, 7, 1894, 1902, The Chemical Society of Japan, 15 Jul. 2021, [Peer-reviewed], [Domestic magazines]
  Scientific journal
• [Ag23Pd2(PPh3)10Cl7]0: A new family of synthesizable bi-icosahedral superatomic molecules
  Sakiat Hossain; Sayuri Miyajima; Takeshi Iwasa; Ryo Kaneko; Taishu Sekine; Ayaka Ikeda; Tokuhisa Kawawaki; Tetsuya Taketsugu; Yuichi Negishi
  The Journal of Chemical Physics, 155, 2, 024302, 024302, AIP Publishing, 14 Jul. 2021, [Peer-reviewed], [Invited], [International Magazine]
  Scientific journal
• Photoluminescence of Doped Superatoms M@Au12 (M = Ru, Rh, Ir) Homoleptically Capped by (Ph2)PCH2P(Ph2): Efficient Room-Temperature Phosphorescence from Ru@Au12
  Shinjiro Takano; Haru Hirai; Takuya Nakashima; Takeshi Iwasa; Tetsuya Taketsugu; Tatsuya Tsukuda
  Journal of the American Chemical Society, 143, 28, 10560, 10564, American Chemical Society (ACS), 07 Jul. 2021, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Single-molecule laser nanospectroscopy with micro–electron volt energy resolution
  Hiroshi Imada; Miyabi Imai-Imada; Kuniyuki Miwa; Hidemasa Yamane; Takeshi Iwasa; Yusuke Tanaka; Naoyuki Toriumi; Kensuke Kimura; Nobuhiko Yokoshi; Atsuya Muranaka; Masanobu Uchiyama; Tetsuya Taketsugu; Yuichiro K. Kato; Hajime Ishihara; Yousoo Kim
  Science, 373, 6550, 95, 98, American Association for the Advancement of Science (AAAS), 02 Jul. 2021, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Ways to characterize and control excited states at the single-molecule and atomic levels are needed to exploit excitation-triggered energy-conversion processes. Here, we present a single-molecule spectroscopic method with micro–electron volt energy and submolecular-spatial resolution using laser driving of nanocavity plasmons to induce molecular luminescence in scanning tunneling microscopy. This tunable and monochromatic nanoprobe allows state-selective characterization of the energy levels and linewidths of individual electronic and vibrational quantum states of a single molecule. Moreover, we demonstrate that the energy levels of the states can be finely tuned by using the Stark effect and plasmon-exciton coupling in the tunneling junction. Our technique and findings open a route to the creation of designed energy-converting functions by using tuned energy levels of molecular systems.
• Delayed Ring-Opening in 1,3-Cyclohexadiene upon Photoexcitation to a Higher State Probed by Time-Resolved Soft X-Ray Absorption
  Y. Kurimoto; N. Saito; Y. Ishii; T. Kanai; J. Itatani; K. Saita; T. Taketsugu; T. Sekikawa
  2021 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC), IEEE, 21 Jun. 2021
  International conference proceedings
• Boron nitride for enhanced oxidative dehydrogenation of ethylbenzene
  Rui Han; Jiangyong Diao; Sonu Kumar; Andrey Lyalin; Tetsuya Taketsugu; Gilberto Casillas; Christopher Richardson; Feng Liu; Chang Won Yoon; Hongyang Liu; Xudong Sun; Zhenguo Huang
  Journal of Energy Chemistry, 57, 477, 484, Elsevier BV, Jun. 2021, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Automatic Determination of Buffer Region in Divide-anc-Conquer Quantum Chemical Calculations
  Masato KOBAYASHI; Toshikazu FUJIMORI; Tetsuya TAKETSUGU
  Journal of Computer Chemistry, Japan, 20, 2, 48, 59, Society of Computer Chemistry Japan, May 2021, [Peer-reviewed], [Invited], [Last author], [Domestic magazines]
  Scientific journal
• Heterocyclic Ring‐Opening of Nanographene on Au(111)
  Kewei Sun; Kazuma Sugawara; Andrey Lyalin; Yusuke Ishigaki; Kohei Uosaki; Tetsuya Taketsugu; Takanori Suzuki; Shigeki Kawai
  Angewandte Chemie, 133, 17, 9513, 9518, Wiley, 19 Apr. 2021, [Peer-reviewed], [Corresponding author]
  Scientific journal
• Heterocyclic Ring‐Opening of Nanographene on Au(111)
  Kewei Sun; Kazuma Sugawara; Andrey Lyalin; Yusuke Ishigaki; Kohei Uosaki; Tetsuya Taketsugu; Takanori Suzuki; Shigeki Kawai
  Angewandte Chemie International Edition, 60, 17, 9427, 9432, Wiley, 19 Apr. 2021, [Peer-reviewed], [Corresponding author], [International Magazine]
  Scientific journal
• Energy‐based automatic determination of buffer region in the divide‐and‐conquer second‐order Møller–Plesset perturbation theory
  Toshikazu Fujimori; Masato Kobayashi; Tetsuya Taketsugu
  Journal of Computational Chemistry, 42, 9, 620, 629, Wiley, 05 Apr. 2021, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal
• Catalytic Activity of Gold Clusters Supported on the h-BN/Au(111) Surface for the Hydrogen Evolution Reaction
  Min Gao; Maki Nakahara; Andrey Lyalin; Tetsuya Taketsugu
  The Journal of Physical Chemistry C, 125, 2, 1334, 1344, American Chemical Society (ACS), 21 Jan. 2021, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal
• Effects of support materials and Ir loading on catalytic N2O decomposition properties
  Satoshi Hinokuma; Takeshi Iwasa; Yoshihiro Kon; Tetsuya Taketsugu; Kazuhiko Sato
  Catalysis Communications, 149, 106208, 106208, Elsevier BV, 15 Jan. 2021, [Peer-reviewed], [International Magazine]
  Scientific journal
• Coordination Geometrical Effect on Ligand-to-Metal Charge Transfer-Dependent Energy Transfer Processes of Luminescent Eu(III) Complexes
  Pedro Paulo Ferreira da Rosa; Shiori Miyazaki; Haruna Sakamoto; Yuichi Kitagawa; Kiyoshi Miyata; Tomoko Akama; Masato Kobayashi; Koji Fushimi; Ken Onda; Tetsuya Taketsugu; Yasuchika Hasegawa
  The Journal of Physical Chemistry A, 125, 1, 209, 217, American Chemical Society (ACS), 14 Jan. 2021, [Peer-reviewed], [International Magazine]
  Scientific journal
• Real-Time Probing of an Atmospheric Photochemical Reaction by Ultrashort Extreme Ultraviolet Pulses: Nitrous Acid Release from o-Nitrophenol
  Yuki Nitta; Oliver Schalk; Hironori Igarashi; Satoi Wada; Takuro Tsutsumi; Kenichiro Saita; Tetsuya Taketsugu; Taro Sekikawa
  The Journal of Physical Chemistry Letters, 12, 1, 674, 679, American Chemical Society (ACS), 14 Jan. 2021, [Peer-reviewed], [International Magazine]
  Scientific journal
• Theoretical method for near-field Raman spectroscopy with multipolar Hamiltonian and real-time-TDDFT: Application to on- and off-resonance tip-enhanced Raman spectroscopy
  Masato Takenaka; Tetsuya Taketsugu; Takeshi Iwasa
  The Journal of Chemical Physics, 154, 2, 024104, 024104, AIP Publishing, 14 Jan. 2021, [Peer-reviewed], [International Magazine]
  Scientific journal
• Geometric analysis of anharmonic downward distortion following paths
  Shuichi Ebisawa; Takuro Tsutsumi; Tetsuya Taketsugu
  Journal of Computational Chemistry, 42, 1, 27, 39, Wiley, 05 Jan. 2021, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal
• Real-time Probing of an Atmospheric Photochemical Reaction by Ultrashort EUV Pulses: Nitrous Acid Release from o-Nitrophenol
  Yuki Nitta; Oliver Schalk; Hironori Igarashi; Satoi Wada; Takuro Tsutsumi; Kenichiro Saita; Tetsuya Taketsugu; Taro Sekikawa
  Conference on Lasers and Electro-Optics, OSA, 2021
  International conference proceedings
• N2O decomposition properties of Ru catalysts supported on various oxide materials and SnO2
  Satoshi Hinokuma; Takeshi Iwasa; Yoshihiro Kon; Tetsuya Taketsugu; Kazuhiko Sato
  Scientific Reports, 10, 1, 21605, Springer Science and Business Media LLC, Dec. 2020, [Peer-reviewed], [International Magazine]
  Scientific journal, Nitrous oxide (N₂O) is a stratospheric ozone depleting greenhouse gas that has global warming potential. As the catalytic decomposition of N₂O is one of the most promising techniques for N₂O emissions abatement, in this study, for this purpose the properties of Ru supported on various oxide materials were investigated under excess O₂ conditions, and the identities of the N₂O adsorption species on the catalysts were confirmed. To clarify the correlation between the catalytic properties and N₂O decomposition activity, the supported Ru catalysts were characterised by means of powder X-ray diffraction, X-ray fluorescence measurements, energy-dispersive X-ray mapping and several gas sorption techniques. The results showed that the redox properties for Ru (RuO₂) at low temperature are closely associated with N₂O decomposition activity. The local structures, optimal Ru loading and N₂O adsorption species of the novel Ru/SnO₂ catalysts were studied and they showed high activity for N₂O decomposition.
• All-electron relativistic spin–orbit multireference computation to elucidate the ground state of CeH
  Yusuke Kondo; Yuri Goto; Masato Kobayashi; Tomoko Akama; Takeshi Noro; Tetsuya Taketsugu
  Physical Chemistry Chemical Physics, 22, 46, 27157, 27162, Royal Society of Chemistry (RSC), 05 Nov. 2020, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal,

  The all-electron relativistic spin–orbit multiconfiguration/multireference computations with the Sapporo basis sets were carried out to elucidate the characters of the low-lying quasi-degenerate electronic states for the CeH diatomic molecule.

• Ammonia Combustion Properties of Copper Oxides-based Honeycomb and Granular Catalysts
  Satoshi HINOKUMA; Takeshi IWASA; Kento ARAKI; Yusuke KAWABATA; Shun MATSUKI; Tetsuya SATO; Yoshihiro KON; Tetsuya TAKETSUGU; Kazuhiko SATO; Masato MACHIDA
  Journal of the Japan Petroleum Institute, 63, 5, 274, 281, Japan Petroleum Institute, 01 Sep. 2020, [Peer-reviewed], [Domestic magazines]
  Scientific journal
• Theoretical and Experimental Studies on the Near‐Infrared Photoreaction Mechanism of a Silicon Phthalocyanine Photoimmunotherapy Dye: Photoinduced Hydrolysis by Radical Anion Generation
  Masato Kobayashi; Mei Harada; Hideo Takakura; Kanta Ando; Yuto Goto; Takao Tsuneda; Mikako Ogawa; Tetsuya Taketsugu
  ChemPlusChem, 85, 9, 1959, 1963, Wiley, Sep. 2020, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Invited for this month's cover are the collaborating groups of Dr. Masato Kobayashi and Prof. Mikako Ogawa, both from Hokkaido University, Sapporo, Japan. The cover picture shows the photochemical reaction process of the near-infrared (NIR) photoimmunotherapy dye IR700, and subsequent cancer cell death. A computational study predicted that ligand dissociation, which is known to initiate cancer cell death, proceeds by the hydrolysis of the IR700 radical anion, rather than as a direct result of NIR irradiation. This mechanism has also been supported by experimental work. Read the full text of the Communication at 10.1002/cplu.202000338.
• Visualization of the Dynamics Effect: Projection of on-the-Fly Trajectories to the Subspace Spanned by the Static Reaction Path Network
  Takuro Tsutsumi; Yuriko Ono; Zin Arai; Tetsuya Taketsugu
  Journal of Chemical Theory and Computation, 16, 7, 4029, 4037, 14 Jul. 2020, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Chitosan, magnetite, silicon dioxide, and graphene oxide nanocomposites: Synthesis, characterization, efficiency as cisplatin drug delivery, and DFT calculations
  Ahmed S. Abdel-Bary; Dina A. Tolan; Mostafa Y. Nassar; Tetsuya Taketsugu; Ahmed M. El-Nahas
  International Journal of Biological Macromolecules, 154, 621, 633, Elsevier BV, Jul. 2020, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Photoinduced Pyramidal Inversion Behavior of Phosphanes Involved with Aggregation‐Induced Emission Behavior
  Takashi Machida; Takeshi Iwasa; Tetsuya Taketsugu; Kazuki Sada; Kenta Kokado
  Chemistry – A European Journal, 26, 36, 8028, 8034, 26 Jun. 2020, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Trajectory on‐the‐fly molecular dynamics approach to tunneling splitting in the electronic excited state: A case of tropolone
  Yusuke Ootani; Aya Satoh; Yu Harabuchi; Tetsuya Taketsugu
  Journal of Computational Chemistry, 41, 16, 1549, 1556, Wiley, 15 Jun. 2020, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal
• A quantum chemical study of substituent effects on CN bonds in aryl isocyanide molecules adsorbed on the Pt surface
  Ben Wang; Min Gao; Kohei Uosaki; Tetsuya Taketsugu
  Physical Chemistry Chemical Physics, 22, 21, 12200, 12208, Royal Society of Chemistry (RSC), 06 May 2020, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal,

  A periodicity implemented scheme of NBO theory and normal mode analysis has been employed to investigate the chemical bond strength tendency for aryl isocyanide molecules with different para-substituted groups adsorbed on the Pt(111) surface.

• Combined computational quantum chemistry and classical electrodynamics approach for surface enhanced infrared absorption spectroscopy
  Masato Takenaka; Tetsuya Taketsugu; Takeshi Iwasa
  The Journal of Chemical Physics, 152, 16, 164103, 164103, AIP Publishing, 30 Apr. 2020, [Peer-reviewed], [International Magazine]
  Scientific journal
• Effect of O2 adsorption on the termination of Li–O2 batteries discharge
  Jiade Li; Min Gao; Shengfu Tong; Cuiping Luo; Huaiyong Zhu; Tetsuya Taketsugu; Kohei Uosaki; Mingmei Wu
  Electrochimica Acta, 340, 135977, 135977, Elsevier BV, Apr. 2020, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Observations and theories of quantum effects in proton transfer electrode processes
  Ken Sakaushi; Andrey Lyalin; Tetsuya Taketsugu
  Current Opinion in Electrochemistry, 19, 96, 105, Elsevier BV, Feb. 2020, [Peer-reviewed], [Invited], [Last author], [International Magazine]
  Scientific journal
• Single-molecule resonance Raman effect in a plasmonic nanocavity
  Jaculbia, R.B; Imada, H; Miwa, K; Iwasa, T; Takenaka, M; Yang, B; Kazuma, E; Hayazawa, N; Taketsugu, T; Kim, Y
  Nature Nanotechnology, 15, 105, 110, 20 Jan. 2020, [Peer-reviewed], [International Magazine]
  Scientific journal
• Theoretical and Experimental Studies on the Near-Infrared Photoreaction Mechanism of a Silicon Phthalocyanine Photoimmunotherapy Dye: Photoinduced Hydrolysis by Radical Anion Generation
  Masato Kobayashi; Mei Harada; Hideo Takakura; Kanta Ando; Yuto Goto; Takao Tsuneda; Mikako Ogawa; Tetsuya Taketsugu
  ChemPlusChem, Wiley-VCH Verlag, 2020
  English, Scientific journal
• Single-Phase Borophene on Ir(111): Formation, Structure, and Decoupling from the Support
  Nikolay A. Vinogradov; Andrey Lyalin; Tetsuya Taketsugu; Alexander S. Vinogradov; Alexei Preobrajenski
  ACS Nano, 13, 12, 14511, 14518, American Chemical Society (ACS), 24 Dec. 2019, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Surface Adsorption Model Calculation Database and Its Application to Activity Prediction of Heterogeneous Catalysts
  Masato KOBAYASHI; Haruka ONODA; Yusuke KURODA; Tetsuya TAKETSUGU
  Journal of Computer Chemistry, Japan, 18, 5, 251, 253, Society of Computer Chemistry Japan, Dec. 2019, [Peer-reviewed], [Last author], [Domestic magazines]
  Scientific journal
• Roles of silver nanoclusters in surface-enhanced Raman spectroscopy
  Takao Tsuneda; Takeshi Iwasa; Tetsuya Taketsugu
  The Journal of Chemical Physics, 151, 9, 094102, 094102, AIP Publishing, 07 Sep. 2019, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal
• Additive‐dependent iptycene incorporation in polyanilines: Insights into the pentiptycene clipping effect and the polymerization mechanism
  Wei Shyang Tan; Ting‐Yin Lee; Sheng‐Fang Tseng; Ying‐Feng Hsu; Masanori Ebina; Tetsuya Taketsugu; Shing‐Jong Huang; Jye‐Shane Yang
  Journal of the Chinese Chemical Society, 66, 9, 1141, 1156, Wiley, Sep. 2019, [Peer-reviewed], [Invited], [Corresponding author], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Anharmonic vibrational computations with a quartic force field for curvilinear coordinates
  Yu Harabuchi; Ryosuke Tani; Nuwan De Silva; Bosiljka Njegic; Mark S. Gordon; Tetsuya Taketsugu
  The Journal of Chemical Physics, 151, 6, 064104, 064104, AIP Publishing, 14 Aug. 2019, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal
• Synthesis of polyaminophosphonic acid-functionalized poly(glycidyl methacrylate) for the efficient sorption of La(III) and Y(III)
  Ahmed A. Galhoum; Emad A. Elshehy; Dina A. Tolan; Ahmed M. El-Nahas; Tetsuya Taketsugu; Kaoru Nishikiori; Takaya Akashi; Asmaa S. Morshedy; Eric Guibal
  Chemical Engineering Journal, 375, 121932-1, 121932-16, Jun. 2019, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Suppression of Pyrite Oxidation by Ferric-catecholate Complexes: An Electrochemical Study
  Xinlong Li; Min Gao; Naoki Hiroyoshi; Carlito Baltazar Tabelin; Tetsuya Taketsugu; Mayumi Ito
  Minerals Engineering, 138, 226, 237, May 2019, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Photoluminescence Properties of [Core+ exo]-Type Au6 Clusters: Insights into the Effect of Ligand Environments on the Excitation Dynamics
  Yukatsu Shichibu; Mingzhe Zhang; Takeshi Iwasa; Yuriko Ono; Tetsuya Taketsugu; Shun Omagari; Takayuki Nakanishi; Yasuchika Hasegawa; Katsuaki Konishi
  Journal of Physical Chemistry C, 123, 11, 6934, 6939, 21 Mar. 2019, [Peer-reviewed], [International Magazine]
  Scientific journal
• 量子化学計算を用いた光免疫療法における細胞障害メカニズムの検討
  原田 芽生; 小林 正人; 安藤 完太; 高倉 栄男; 武次 徹也; 小川 美香子
  日本薬学会年会要旨集, 139年会, 2, 80, 80, (公社)日本薬学会, Mar. 2019
  Japanese
• Low-Lying Excited States of hqxcH and Zn-hqxc Complex: Toward Understanding Intramolecular Proton Transfer Emission
  Ebina Masanori; Kondo Yusuke; Iwasa Takeshi; Taketsugu Tetsuya
  INORGANIC CHEMISTRY, 58, 7, 4686, 4698, Mar. 2019, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
• Ammonia-rich combustion and ammonia combustive decomposition properties of various supported catalysts
  Hinokuma Satoshi; Araki Kento; Iwasa Takeshi; Kiritoshi Saaya; Kawabata Yusuke; Taketsugu Tetsuya; Machida Masato
  CATALYSIS COMMUNICATIONS, 123, 64, 68, Feb. 2019, [Peer-reviewed], [International Magazine]
• Ab initio surface hopping molecular dynamics on the dissociative recombination of CH3+
  Tetsuya Taketsugu; Yuta Kobayashi
  Computational and Theoretical Chemistry, 1150, 1, 9, Elsevier BV, Feb. 2019, [Peer-reviewed], [Invited], [Lead author, Corresponding author], [International Magazine]
  Scientific journal
• Soft X-ray Li-K and Si-L-2,L-3 Emission from Crystalline and Amorphous Lithium Silicides in Lithium-Ion Batteries Anode
  Lyalin Andrey; Kuznetsov Vladimir G; Nakayama Akira; Abarenkov Igor V; Tupitsyn Ilya I; Gabis Igor E; Uosaki Kohei; Taketsugu Tetsuya
  JOURNAL OF THE ELECTROCHEMICAL SOCIETY, 166, 3, A5362, A5368, 19 Jan. 2019, [Peer-reviewed], [Last author], ［Internationally co-authored］, [International Magazine]
• Ab initio surface hopping excited‐state molecular dynamics approach on the basis of spin–orbit coupled states: An application to the A‐band photodissociation of CH 3 I
  Muneaki Kamiya; Tetsuya Taketsugu
  Journal of Computational Chemistry, 40, 2, 456, 463, Wiley, 15 Jan. 2019, [Peer-reviewed], [Invited], [Last author, Corresponding author], [International Magazine]
  Scientific journal
• Vibrational symmetry of a single molecule revealed by tip-enhanced Raman spectroscopy
  Rafael B. Jaculbia; Hiroshi Imada; Kuniyuki Miwa; Takeshi Iwasa; Masato Takenaka; Bo Yang; Emiko Kazuma; Norihiko Hayazawa; Tetsuya Taketsugu; Yousoo Kim
  Optics InfoBase Conference Papers, Part F146-JSAP 2019, 2019
  International conference proceedings
• Structural and Electronic Properties, Isomerization, and NO Dissociation Reactions on Au, Ag, Cu Clusters
  Kondo Yusuke; Takahara Rina; Mohri Hirono; Takagi Makito; Maeda Satoshi; Iwasa Takeshi; Taketsugu Tetsuya
  JOURNAL OF COMPUTER CHEMISTRY-JAPAN, 18, 1, 64, 69, Jan. 2019, [Peer-reviewed], [Invited], [Domestic magazines]
  Japanese, Scientific journal
• The Role of Nitrogen-doping and the Effect of the pH on the Oxygen Reduction Reaction on Highly Active Nitrided Carbon Sphere Catalysts
  Markus Eckardt; Ken Sakaushi; Andrey Lyalin; Maximilian Wassner; Nicola Hüsing; Tetsuya Taketsugu; Rolf Jürgen Behm
  Electrochimica Acta, 299, 736, 748, Jan. 2019, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Synthesis of armchair graphene nanoribbons from the 10,10′-dibromo-9,9′-bianthracene molecules on Ag(111): The role of organometallic intermediates
  K. A. Simonov; A. V. Generalov; A. S. Vinogradov; G. I. Svirskiy; A. A. Cafolla; C. McGuinness; T. Taketsugu; A. Lyalin; N. Mårtensson; A. B. Preobrajenski
  Scientific Reports, 8, 1, 3506, Nature Publishing Group, 01 Dec. 2018, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Combined Automated Reaction Pathway Searches and Sparse Modeling Analysis for Catalytic Properties of Lowest Energy Twins of Cu13
  Takeshi Iwasa; Takaaki Sato; Makito Takagi; Min Gao; Andrey Lyalin; Masato Kobayashi; Ken-ichi Shimizu; Satoshi Maeda; Tetsuya Taketsugu
  The Journal of Physical Chemistry A, 123, 1, 210, 217, Dec. 2018, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal, In nanocatalysis, growing attention has recently been given to investigation of energetically low-lying structural isomers of atomic clusters, because some isomers can demonstrate better catalytic activity than the most stable structures. In this study, we present a comparative investigation of catalytic activity for NO dissociation of a pair of the energetically degenerated isomers of Cu13 cluster having C2 and C s symmetries. It is shown that although these isomers have similar structural, electronic, and optical properties, they can possess very different catalytic activities. The effect of isomerization between cluster isomers is considered using state-of-the-art automated reaction pathway search techniques such as an artificial force induced reaction (AFIR) method as a part of a global reaction route mapping (GRRM) strategy. This method allows effectively to locate a large number of possible reaction pathways and transition states (TSs). In total, 12 TSs for NO dissociation were obtained for Cu13, of C2, C s, as well as I h isomers. Sparse modeling analysis shows that LUMO is strongly negatively correlated with total energy of TSs. For most TSs, LUMO has the antibonding character of NO, consisting of the interaction between π* of NO and SOMO of Cu13. Therefore, an increase in the strength of interaction between NO molecule and Cu13 cluster causes the rise in energy of the LUMO, resulting in lowering of the TS energy for NO dissociation. The combination of the automated reaction pathway search technique and sparse modeling represents a powerful tool for analysis and prediction of the physicochemical properties of atomic clusters, especially in the regime of structural fluxionality, where traditional methods based on random geometry search analyses are difficult.
• CO2 Adsorption on Ti3O6ˉ: A Novel Carbonate Binding Motif
  Sreekanta Debnath; Xiaowei Song; Matias Fagiani; Marissa Weichman; Min Gao; Satoshi Maeda; Tetsuya Taketsugu; Wieland Schöllkopf; Andrey Lyalin; Daniel Neumark; Knut Asmis
  The Journal of Physical Chemistry C, 123, 8439, 8446, Dec. 2018, [Peer-reviewed], [Invited], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Supported binary CuOx−Pt catalysts with high activity and thermal stability for the combustion of NH3 as a carbon-free energy source
  Saaya Kiritoshi; Takeshi Iwasa; Kento Araki; Yusuke Kawabata; Tetsuya Taketsugu; Satoshi Hinokuma; Masato Machida
  RSC Advances, 8, 41491, 41498, Dec. 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Dispersion Interaction and Crystal Packing Realize the Ultralong C-C Single Bond: A Theoretical Study on Dispirobis(10-methylacridan) Derivatives
  Yusuke Kuroda; Masato Kobayashi; Tetsuya Taketsugu
  Chemistry Letters, 48, 2, 137, 139, The Chemical Society of Japan, Dec. 2018, [Peer-reviewed], [Last author], [Domestic magazines]
  English, Scientific journal
• Quantum-to-Classical Transition of Proton-Transfer in Potential-Induced Dioxygen Reduction
  Ken Sakaushi; Andrey Lyalin; Tetsuya Taketsugu; Kohei Uosaki
  Physical Review Letters, 121, 236001, Dec. 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• First principles calculations toward understanding SERS of 2,2′-bipyridyl adsorbed on Au, Ag and Au-Ag alloy
  Masato Takenaka; Yoshikazu Hashimoto; Takeshi Iwasa; Tetsuya Taketsugu; Gediminas Seniutinas; Armandas Balčytis; Saulius Juodkazise; Yoshiaki Nishijima
  Journal of Computational Chemistry, 40, 925, 932, Oct. 2018, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
• Theoretical investigations on hydrogen peroxide decomposition in aquo
  Takao Tsuneda; Tetsuya Taketsugu
  Physical Chemistry Chemical Physics, 20, 24992, 24999, Sep. 2018, [Peer-reviewed], [International Magazine]
• Theoretical suggestion and experimental proof for functionalization of h-BN by gold as electrocatalysts for ORR and HER
  Taketsugu Tetsuya; Lyalin Andrey; Gao Min; Uosaki Kohei
  ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 256, 19 Aug. 2018, [Peer-reviewed]
• Spiral Eu(III) Coordination Polymers with Circularly Polarized Luminescence
  Yasuchika Hasegawa; Yui Miura; Yuichi Kitagawa; Satoshi Wada; Takayuki Nakanishi; Koji Fushimi; Tomohiro Seki; Hajime Ito; Takeshi Iwasa; Tetsuya Taketsugu; Masayuki Gon; Kazuo Tanaka; Yoshiki Chujo; Shingo Hattori; Masanobu Karasawa; Kazuyuki Ishii
  ChemComm, 54, 10695, 10697, Aug. 2018, [Peer-reviewed], [Invited], [International Magazine]
• On-the-fly molecular dynamics study of the excited-state branching reaction of α-methyl-cis-stilbene
  Takuro Tsutsumi; Yu Harabuchi; Rina Yamamoto; Satoshi Maeda; Tetsuya Taketsugu
  Chemical Physics, 515, 564, 571, Aug. 2018, [Peer-reviewed], [Invited], [International Magazine]
  English, Scientific journal
• Defect-induced efficient dry reforming of methane over two-dimensional Ni/h-boron nitride nanosheet catalysts
  Yang Cao; Phornphimon Maitarad; Min Gao; Tetsuya Taketsugu; Hongrui Li; Tingting Yan; Liyi Shi; Dengsong Zhang
  Applied Catalysis B: Environmental, 238, 51, 60, Jul. 2018, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
• Microscopic Electrode Processes in the Four-Electron Oxygen Reduction on Highly Active Carbon-Based Electrocatalysts
  Ken Sakaushi; Markus Eckardt; Andrey Lyalin; Tetsuya Taketsugu; R. Jurgen Behm; Kohei Uosaki
  ACS Catalysis, 8, 8162, 8176, American Chemical Society ({ACS}), Jul. 2018, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
• Visualization of the Intrinsic Reaction Coordinate and Global Reaction Route Map by Classical Multidimensional Scaling
  Takuro Tsutsumi; Yuriko Ono; Zin Arai; Tetsuya Taketsugu
  Journal of Chemical Theory and Computation, 14, 8, 4263, 4270, American Chemical Society ({ACS}), Jul. 2018, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal
• All-electron relativistic computations on the low-lying electronic states, bond length, and vibrational frequency of CeF diatomic molecule with spin–orbit coupling effects
  Yusuke Kondo; Masato Kobayashi; Tomoko Akama; Takeshi Noro; Tetsuya Taketsugu
  Journal of Computational Chemistry, 39, 16, 964, 972, John Wiley and Sons Inc., 15 Jun. 2018, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Automated error control in divide-and-conquer self-consistent field calculations
  Masato Kobayashi; Toshikazu Fujimori; Tetsuya Taketsugu
  Journal of Computational Chemistry, 39, 15, 909, 916, John Wiley and Sons Inc., 05 Jun. 2018, [Peer-reviewed], [Last author], [International Magazine]
  English, Scientific journal
• Lithiation Products of a Silicon Anode Based on Soft X-ray Emission Spectroscopy: A Theoretical Study
  Andrey Lyalin; Vladimir G. Kuznetsov; Akira Nakayama; Igor V. Abarenkov; Ilya I. Tupitsyn; Igor E. Gabis; Kohei Uosaki; Tetsuya Taketsugu
  The Journal of Physical Chemistry C, 122, 20, 11096, 11108, American Chemical Society, 24 May 2018, [Peer-reviewed], [Last author], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Insights into geometries, stabilities, electronic structures, reactivity descriptors, and magnetic properties of bimetallic Ni m Cu n-m (m = 1, 2; n = 3-13) clusters: Comparison with pure copper clusters
  Raman K. Singh; Takeshi Iwasa; Tetsuya Taketsugu
  Journal of Computational Chemistry, 39, 1878, 1889, May 2018, [Peer-reviewed], [Last author, Corresponding author], ［Internationally co-authored］, [International Magazine]
• Different photoisomerization routes found in the structural isomers of hydroxy methylcinnamate
  Shin-nosuke Kinoshita; Yasunori Miyazaki; Masataka Sumida; Yuuki Onitsuka; Hiroshi Kohguchi; Yoshiya Inokuchi; Nobuyuki Akai; Takafumi Shiraogawa; Masahiro Ehara; Kaoru Yamazaki; Yu Harabuchi; Satoshi Maeda; Tetsuya Taketsugu; Takayuki Ebata
  Physical Chemistry Chemical Physics, 20, 26, 17583, 17598, 06 Apr. 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Oxygen Reduction Reaction Catalyzed by Small Gold Cluster on h-BN/Au(111) Support
  Andrey Lyalin; Kohei Uosaki; Tetsuya Taketsugu
  Electrocatalysis, 9, 2, 182, 188, Springer New York LLC, 01 Mar. 2018, [Peer-reviewed], [Last author], [International Magazine]
  English, Scientific journal
• Time-Dependent Density Functional Theory Study on Higher Low-Lying Excited States of Au25(SR)18 -
  Masanori Ebina; Takeshi Iwasa; Yu Harabuchi; Tetsuya Taketsugu
  The Journal of Physical Chemistry C, 122, 7, 4097, 4104, American Chemical Society, 22 Feb. 2018, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Fundamental peak disappears upon binding of a noble gas: A case of the vibrational spectrum of PtCO in an argon matrix
  Yuriko Ono; Kiyoshi Yagi; Toshiyuki Takayanagi; Tetsuya Taketsugu
  Physical Chemistry Chemical Physics, 20, 5, 3296, 3302, Royal Society of Chemistry, 07 Feb. 2018, [Peer-reviewed], [Invited], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Theoretical study of initial reactions of amine (CH3)nNH(3− n ) (n = 1, 2, 3) with ozone
  Ayako Furuhama; Takashi Imamura; Satoshi Maeda; Tetsuya Taketsugu
  Chemical Physics Letters, 692, 111, 116, Elsevier B.V., 16 Jan. 2018, [Peer-reviewed], [Last author], [International Magazine]
  English, Scientific journal
• Twist of C=C Bond Plays a Crucial Role in the Quenching of AIE-Active Tetraphenylethene Derivatives in Solution
  Kenta Kokado; Takashi Machida; Takeshi Iwasa; Tetsuya Taketsugu; Kazuki Sada
  Journal of Physical Chemistry C, 122, 1, 245, 251, American Chemical Society, 11 Jan. 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Analyses of trajectory on-the-fly based on the global reaction route map
  Takuro Tsutsumi; Yu Harabuchi; Yuriko Ono; Satoshi Maeda; Tetsuya Taketsugu
  Physical Chemistry Chemical Physics, 20, 3, 1364, 1372, Royal Society of Chemistry, 2018, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Optical readout of hydrogen storage in films of Au and Pd
  Yoshiaki Nishijima; Shogo Shimizu; Keisuke Kurihara; Yoshikazu Hashimoto; Hajime Takahashi; Armandas Balcytis; Gediminas Seniutinas; Shinji Okazaki; Jurga Juodkazyte; Takeshi Iwasa; Tetsuya Taketsugu; Yoriko Tominaga; Saulius Juodkazis
  OPTICS EXPRESS, 25, 20, 24081, 24092, Oct. 2017, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Enhanced Luminescence of Asymmetrical Seven-Coordinate Eu-III Complexes Including LMCT Perturbation
  Kei Yanagisawa; Yuichi Kitagawa; Takayuki Nakanishi; Tomoko Akama; Masato Kobayashi; Tomohiro Seki; Koji Fushimi; Hajime Ito; Tetsuya Taketsugu; Yasuchika Hasegawa
  EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, 2017, 32, 3843, 3848, Sep. 2017, [Peer-reviewed], [Invited], [International Magazine]
  English, Scientific journal
• Excess charge driven dissociative hydrogen adsorption on Ti2O4-
  Xiaowei Song; Matias R. Fagiani; Sreekanta Debnath; Min Gao; Satoshi Maeda; Tetsuya Taketsugu; Sandy Gewinner; Wieland Schoellkopf; Knut R. Asmis; Andrey Lyalin
  PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 19, 34, 23154, 23161, Sep. 2017, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Solvent effects on the excited-state double proton transfer mechanism in the 7-azaindole dimer: a TDDFT study with the polarizable continuum model
  Xue-fang Yu; Shohei Yamazaki; Tetsuya Taketsugu
  PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 19, 34, 23289, 23301, Sep. 2017, [Peer-reviewed], [Last author], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Transition-Metal-Free Boryl Substitution Using Silylboranes and Alkoxy Bases
  Eiji Yamamoto; Satoshi Maedab; Tetsuya Taketsugub; Hajime Ito
  SYNLETT, 28, 11, 1258, 1267, Jul. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• An autocatalytic cycle in autoxidation of triethylborane
  Ryohei Uematsu; Chihiro Saka; Yosuke Sumiya; Tomoya Ichino; Tetsuya Taketsugu; Satoshi Maeda
  CHEMICAL COMMUNICATIONS, 53, 53, 7302, 7305, Jul. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Exploring the full catalytic cycle of rhodium(I)BINAP-catalysed isomerisation of allylic amines: a graph theory approach for path optimisation
  Takayoshi Yoshimura; Satoshi Maeda; Tetsuya Taketsugu; Masaya Sawamura; Keiji Morokuma; Seiji Mori
  CHEMICAL SCIENCE, 8, 6, 4475, 4488, Jun. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Global search for low-lying crystal structures using the artificial force induced reaction method: A case study on carbon
  Makito Takagi; Tetsuya Taketsugu; Hiori Kino; Yoshitaka Tateyama; Kiyoyuki Terakura; Satoshi Maeda
  PHYSICAL REVIEW B, 95, 18, 184110, May 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Luminescent Mechanochromic 9-Anthryl Gold(I) Isocyanide Complex with an Emission Maximum at 900 nm after Mechanical Stimulation
  Tomohiro Seki; Noriaki Tokodai; Shun Omagari; Takayuki Nakanishi; Yasuchika Hasegawa; Takeshi Iwasa; Tetsuya Taketsugu; Hajime Ito
  JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 139, 19, 6514, 6517, May 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Combined gradient projection/single component artificial force induced reaction (GP/SC-AFIR) method for an efficient search of minimum energy conical intersection (MECI) geometries
  Yu Harabuchi; Tetsuya Taketsugu; Satoshi Maeda
  CHEMICAL PHYSICS LETTERS, 674, 141, 145, Apr. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Isomerization in Gold Clusters upon O-2 Adsorption
  Min Gao; Daisuke Horita; Yuriko Ono; Andrey Lyalin; Satoshi Maeda; Tetsuya Taketsugu
  THE JOURNAL OF PHYSICAL CHEMISTRY C, 121, 5, 2661, 2668, Feb. 2017, [Peer-reviewed], [Invited], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Interface Effects in Hydrogen Elimination Reaction from Isopropanol by Ni-13 Cluster on theta-Al2O3(010) Surface
  Andrey Lyalin; Ken-ichi Shimizu; Tetsuya Taketsugu
  THE JOURNAL OF PHYSICAL CHEMISTRY C, 121, 6, 3488, 3495, Feb. 2017, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Two-Dimensional Corrugated Porous Carbon-, Nitrogen-Framework/Metal Heterojunction for Efficient Multielectron Transfer Processes with Controlled Kinetics
  Ken Sakaushi; Andrey Lyalin; Satoshi Tominaka; Tetsuya Taketsugu; Kohei Uosaki
  ACS NANO, 11, 2, 1770, 1779, Feb. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Controlling the Relaxation Pathways by Substituent Effects in Conjugated Dienes
  Tateharu Tentaku; Ryunosuke Atobe; Kotaro Araki; Sota Satoh; Yu Harabuchi; Tetsuya Taketsugu; Taro Sekikawa
  2017 CONFERENCE ON LASERS AND ELECTRO-OPTICS EUROPE & EUROPEAN QUANTUM ELECTRONICS CONFERENCE (CLEO/EUROPE-EQEC), 2017
  English, International conference proceedings
• Atomically Thin Hexagonal Boron Nitride Nanofilm for Cu Protection: The Importance of Film Perfection
  Majharul Haque Khan; Sina S. Jamali; Andrey Lyalin; Paul J. Molino; Lei Jiang; Hua Kun Liu; Tetsuya Taketsugu; Zhenguo Huang
  ADVANCED MATERIALS, 29, 4, 1603937, Jan. 2017, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Full Rate Constant Matrix Contraction Method for Obtaining Branching Ratio of Unimolecular Decomposition
  Yosuke Sumiya; Tetsuya Taketsugu; Satoshi Maeda
  JOURNAL OF COMPUTATIONAL CHEMISTRY, 38, 2, 101, 109, Jan. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Divide-and-Conquer Hartree-Fock-Bogoliubov Method and Its Application to Conjugated Diradical Systems
  Masato Kobayashi; Tetsuya Taketsugu
  CHEMISTRY LETTERS, 45, 11, 1268, 1270, Nov. 2016, [Peer-reviewed], [Last author], [Domestic magazines]
  English, Scientific journal
• Ab Initio Molecular Dynamics Study of the Photoreaction of 1,1 '-Dimethylstilbene upon S-0 -> S-1 Excitation
  Yu Harabuchi; Rina Yamamoto; Satoshi Maeda; Satoshi Takeuchi; Tahei Tahara; Tetsuya Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY A, 120, 44, 8804, 8812, Nov. 2016, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Ab initio Molecular Dynamics Study of H-2 Formation inside POSS Compounds. 2. The Effect of an Encapsulated Hydrogen Molecule
  Takako Kudo; Tetsuya Taketsugu; Mark S. Gordon
  JOURNAL OF PHYSICAL CHEMISTRY A, 120, 43, 8699, 8715, Nov. 2016, [Peer-reviewed], [Invited], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Multistep Intersystem Crossing Pathways in Cinnamate-Based UV-B Sunscreens
  Kaoru Yamazaki; Yasunori Miyazaki; Yu Harabuchi; Tetsuya Taketsugu; Satoshi Maeda; Yoshiya Inokuchi; Shin-nosuke Kinoshita; Masataka Sumida; Yuuki Onitsuka; Hiroshi Kohguchi; Masahiro Ehara; Takayuki Ebata
  The Journal of Physical Chemistry Letters, 7, 19, 4001, 4007, 06 Oct. 2016, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Artificial Force Induced Reaction (AFIR) Method for Exploring Quantum Chemical Potential Energy Surfaces
  Satoshi Maeda; Yu Harabuchi; Makito Takagi; Tetsuya Taketsugu; Keiji Morokuma
  CHEMICAL RECORD, 16, 5, 2232, 2248, Oct. 2016, [Peer-reviewed], [Invited], [International Magazine]
  English, Scientific journal
• When Inert Becomes Active: A Fascinating Route for Catalyst Design
  Andrey Lyalin; Min Gao; Tetsuya Taketsugu
  CHEMICAL RECORD, 16, 5, 2324, 2337, Oct. 2016, [Peer-reviewed], [Invited], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Catalytic Hydrogenation of Carbon Dioxide with Ammonia-Borane by Pincer-Type Phosphorus Compounds: Theoretical Prediction
  Guixiang Zeng; Satoshi Maeda; Tetsuya Taketsugu; Shigeyoshi Sakaki
  JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 138, 41, 13481, 13484, Oct. 2016, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Nonadiabatic Pathways of Furan and Dibenzofuran: What Makes Dibenzofuran Fluorescent?
  Yu Harabuchi; Tetsuya Taketsugu; Satoshi Maeda
  CHEMISTRY LETTERS, 45, 8, 940, 942, Aug. 2016, [Peer-reviewed], [Domestic magazines]
  English, Scientific journal
• Theoretical Study of Hydrogenation Catalysis of Phosphorus Compound and Prediction of Catalyst with High Activity and Wide Application Scope
  Guixiang Zeng; Satoshi Maeda; Tetsuya Taketsugu; Shigeyoshi Sakaki
  ACS CATALYSIS, 6, 8, 4859, 4870, Aug. 2016, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Highly Efficient Electrochemical Hydrogen Evolution Reaction at Insulating Boron Nitride Nanosheet on Inert Gold Substrate
  Kohei Uosaki; Ganesan Elumalai; Hung Cuong Dinh; Andrey Lyalin; Tetsuya Taketsugu; Hidenori Noguchi
  SCIENTIFIC REPORTS, 6, 32217, Aug. 2016, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Theoretical study on mechanism of the photochemical ligand substitution of fac-[Re-I(bpy)(CO)(3)(PR3)](+) complex
  Kenichiro Saita; Yu Harabuchi; Tetsuya Taketsugu; Osamu Ishitani; Satoshi Maeda
  PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 18, 26, 17557, 17564, Jul. 2016, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Long Range Functionalization of h-BN Monolayer by Carbon Doping
  Min Gao; Masashi Adachi; Andrey Lyalin; Tetsuya Taketsugu
  THE JOURNAL OF PHYSICAL CHEMISTRY C, 120, 29, 15993, 16001, Jul. 2016, [Peer-reviewed], [Invited], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Core-Structure-Dependent Luminescence of Thiolato-Bridged Copper(I) Cluster Complexes
  Kotaro Shimada; Atsushi Kobayashi; Yuriko Ono; Hiroki Ohara; Tatsuya Hasegawa; Tetsuya Taketsugu; Eri Sakuda; Soichiro Akagi; Noboru Kitamura; Masako Kato
  THE JOURNAL OF PHYSICAL CHEMISTRY C, 120, 29, 16002, 16011, Jul. 2016, [Peer-reviewed], [Invited], [International Magazine]
  English, Scientific journal
• Structural dynamics of photochemical reactions probed by time-resolved photoelectron spectroscopy using high harmonic pulses
  Ryo Iikubo; Taro Sekikawa; Yu Harabuchi; Tetsuya Taketsugu
  Faraday Discussions, 194, 147, 160, 31 May 2016, [Peer-reviewed], [Invited], [Last author], [International Magazine]
  English, Scientific journal
• Gold nanoparticle decoration of insulating boron nitride nanosheet on inert gold electrode toward an efficient electrocatalyst for the reduction of oxygen to water
  Ganesan Elumalai; Hidenori Noguchi; Andrey Lyalin; Tetsuya Taketsugu; Kohei Uosaki
  ELECTROCHEMISTRY COMMUNICATIONS, 66, 53, 57, May 2016, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Exploring the Mechanism of Ultrafast Intersystem Crossing in Rhenium(I) Carbonyl Bipyridine Halide Complexes: Key Vibrational Modes and Spin-Vibronic Quantum Dynamics
  Yu Harabuchi; Julien Eng; Etienne Gindensperger; Tetsuya Taketsugu; Satoshi Maeda; Chantal Daniel
  JOURNAL OF CHEMICAL THEORY AND COMPUTATION, 12, 5, 2335, 2345, May 2016, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Spin-Orbit Coupling Effects on Low-lying Electronic States of PtCN/PtNC and PdCN/PdNC
  Yuriko Ono; Yusuke Kondo; Masato Kobayashi; Tetsuya Taketsugu
  CHEMISTRY LETTERS, 45, 4, 478, 480, Apr. 2016, [Peer-reviewed], [Last author, Corresponding author], [Domestic magazines]
  English, Scientific journal
• Deciphering Time Scale Hierarchy in Reaction Networks
  Yutaka Nagahata; Satoshi Maeda; Hiroshi Teramoto; Takashi Horiyama; Tetsuya Taketsugu; Tamiki Komatsuzaki
  JOURNAL OF PHYSICAL CHEMISTRY B, 120, 8, 1961, 1971, Mar. 2016, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Generalized theoretical method for the interaction between arbitrary nonuniform electric field and molecular vibrations: Toward near-field infrared spectroscopy and microscopy
  Takeshi Iwasa; Masato Takenaka; Tetsuya Taketsugu
  JOURNAL OF CHEMICAL PHYSICS, 144, 12, 124116, Mar. 2016, [Peer-reviewed], [Last author], [International Magazine]
  English, Scientific journal
• Nontotally symmetric trifurcation of an S(N)2 reaction pathway
  Yu Harabuchi; Yuriko Ono; Satoshi Maeda; Tetsuya Taketsugu; Kristopher Keipert; Mark S. Gordon
  JOURNAL OF COMPUTATIONAL CHEMISTRY, 37, 5, 487, 493, Feb. 2016, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• SbおよびTe化合物のリガンド交換・リガンドカップリング反応メカニズム
  小林正人; 黒田悠介; 秋葉欣哉; 武次徹也
  Journal of Computer Chemistry, Japan, 14, 6, 199, 200, Society of Computer Chemistry, Japan, Jan. 2016, [Peer-reviewed], [Last author], [Domestic magazines]
  Japanese, Theoretical and computational studies on the mechanisms of ligand exchange reaction (LER) and ligand coupling reaction (LCR) of hypervalent pentacoordinate Sb and tetracoordinate Te compounds were carried out. Contrary to the previous suggestion from experimentalists, the lone pair electrons of Te do not participate in LER. Also, LER of R₅Sb proceeds via a similar mechanism to that of R₄Te. As for the LCR of R₅Sb, the apical-equatorial coupling mechanism was suggested.
• Contrasting ring-opening propensities in UV-excited alpha-pyrone and coumarin
  Daniel Murdock; Rebecca A. Ingle; Igor V. Sazanovich; Ian P. Clark; Yu Harabuchi; Tetsuya Taketsugu; Satoshi Maeda; Andrew J. Orr-Ewing; Michael N. R. Ashfold
  PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 18, 4, 2629, 2638, Jan. 2016, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Kinetic Analysis for the Multistep Profiles of Organic Reactions: Significance of the Conformational Entropy on the Rate Constants of the Claisen Rearrangement
  Yosuke Sumiya; Yutaka Nagahata; Tamiki Komatsuzaki; Tetsuya Taketsugu; Satoshi Maeda
  The Journal of Physical Chemistry A, 119, 48, 11641, 11649, 03 Dec. 2015, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Theoretical Study on the Mechanism of the Ligand Coupling Reaction of Hypervalent Pentacoordinate Antimony Compounds
  Masato Kobayashi; Yusuke Kuroda; Kin-ya Akiba; Tetsuya Taketsugu
  Bulletin of the Chemical Society of Japan, 88, 11, 1584, 1590, 15 Nov. 2015, [Peer-reviewed], [Last author], [Domestic magazines]
  English, Scientific journal
• Response to “Comment on ‘Analyses of bifurcation of reaction pathways on a global reaction route map: A case study of gold cluster Au5”’ [J. Chem. Phys. 143, 177101 (2015)]
  Yu Harabuchi; Yuriko Ono; Satoshi Maeda; Tetsuya Taketsugu
  The Journal of Chemical Physics, 143, 17, 177102, 177102, 07 Nov. 2015, [Peer-reviewed], [Invited], [Last author, Corresponding author], [International Magazine]
  Scientific journal
• Synthesis of yellow and red fluorescent 1,3a,6a-triazapentalenes and the theoretical investigation of their optical properties
  Kosuke Namba; Ayumi Osawa; Akira Nakayama; Akane Mera; Fumi Tano; Yoshiro Chuman; Eri Sakuda; Tetsuya Taketsugu; Kazuyasu Sakaguchi; Noboru Kitamura; Keiji Tanino
  Chemical Science, 6, 2, 1083, 1093, 23 Oct. 2015, [Peer-reviewed], [International Magazine]
  Scientific journal
• From Graphene Nanoribbons on Cu(111) to Nanographene on Cu(110): Critical Role of Substrate Structure in the Bottom-Up Fabrication Strategy
  Konstantin A. Simonov; Nikolay A. Vinogradov; Alexander S. Vinogradov; Alexander V. Generalov; Elena M. Zagrebina; Gleb I. Svirskiy; Attilio A. Cafolla; Thomas Carpy; John P. Cunniffe; Tetsuya Taketsugu; Andrey Lyalin; Nils Mårtensson; Alexei B. Preobrajenski
  ACS Nano, 9, 9, 8997, 9011, 22 Sep. 2015, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Seven-Coordinate Luminophores: Brilliant Luminescence of Lanthanide Complexes withC3vGeometrical Structures
  Kei Yanagisawa; Takayuki Nakanishi; Yuichi Kitagawa; Tomohiro Seki; Tomoko Akama; Masato Kobayashi; Tetsuya Taketsugu; Hajime Ito; Koji Fushimi; Yasuchika Hasegawa
  European Journal of Inorganic Chemistry, 2015, 28, 4769, 4774, 07 Sep. 2015, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Second-order Møller–Plesset perturbation (MP2) theory at finite temperature: relation with Surján’s density matrix MP2 and its application to linear-scaling divide-and-conquer method
  Masato Kobayashi; Tetsuya Taketsugu
  Theoretical Chemistry Accounts, 134, 9, 107, 107, 15 Aug. 2015, [Peer-reviewed], [Last author], [International Magazine]
  English, Scientific journal
• Exploration of minimum energy conical intersection structures of small polycyclic aromatic hydrocarbons: toward an understanding of the size dependence of fluorescence quantum yields
  Yu Harabuchi; Tetsuya Taketsugu; Satoshi Maeda
  Physical Chemistry Chemical Physics, 17, 35, 22561, 22565, 30 Jul. 2015, [Peer-reviewed], [International Magazine]
  Scientific journal
• Assessment of hybrid, meta-hybrid-GGA, and long-range corrected density functionals for the estimation of enthalpies of formation, barrier heights, and ionisation potentials of selected C1–C5 oxygenates
  Ahmed M. El-Nahas; John M. Simmie; Ahmed H. Mangood; Kimihiko Hirao; Jong-Won Song; Mark A. Watson; Tetsuya Taketsugu; Nobuaki Koga
  Molecular Physics, 113, 13-14, 1630, 1635, 18 Jul. 2015, [Peer-reviewed], [Invited], ［Internationally co-authored］, [International Magazine]
  Scientific journal
• Analyses of bifurcation of reaction pathways on a global reaction route map: A case study of gold cluster Au5
  Yu Harabuchi; Yuriko Ono; Satoshi Maeda; Tetsuya Taketsugu
  The Journal of Chemical Physics, 143, 1, 014301, 014301, 07 Jul. 2015, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Time-Resolved Photoelectron Spectroscopy of Dissociating 1,2-Butadiene Molecules by High Harmonic Pulses
  Ryo Iikubo; Takehisa Fujiwara; Taro Sekikawa; Yu Harabuchi; Sota Satoh; Tetsuya Taketsugu; Yosuke Kayanuma
  The Journal of Physical Chemistry Letters, 6, 13, 2463, 2468, 02 Jul. 2015, [Peer-reviewed], [International Magazine]
  Scientific journal
• Reactivity of Gold Clusters in the Regime of Structural Fluxionality
  Min Gao; Andrey Lyalin; Makito Takagi; Satoshi Maeda; Tetsuya Taketsugu
  The Journal of Physical Chemistry C, 119, 20, 11120, 11130, 21 May 2015, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal
• Reaction Mechanism of the Anomalous Formal Nucleophilic Borylation of Organic Halides with Silylborane: Combined Theoretical and Experimental Studies
  Ryohei Uematsu; Eiji Yamamoto; Satoshi Maeda; Hajime Ito; Tetsuya Taketsugu
  Journal of the American Chemical Society, 137, 12, 4090, 4099, 01 Apr. 2015, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal
• From Roaming Atoms to Hopping Surfaces: Mapping Out Global Reaction Routes in Photochemistry
  Satoshi Maeda; Tetsuya Taketsugu; Koichi Ohno; Keiji Morokuma
  Journal of the American Chemical Society, 137, 10, 3433, 3445, 18 Mar. 2015, [Peer-reviewed], [Invited], [International Magazine]
  English, Scientific journal
• Intrinsic reaction coordinate: Calculation, bifurcation, and automated search
  Satoshi Maeda; Yu Harabuchi; Yuriko Ono; Tetsuya Taketsugu; Keiji Morokuma
  International Journal of Quantum Chemistry, 115, 5, 258, 269, 05 Mar. 2015, [Peer-reviewed], [Invited], [Corresponding author], [International Magazine]
  English, Scientific journal
• Matrix site effects on vibrational frequencies of HXeCCH, HXeBr, and HXeI: a hybrid quantum-classical simulation
  Keisuke Niimi; Tetsuya Taketsugu; Akira Nakayama
  Physical Chemistry Chemical Physics, 17, 12, 7872, 7880, 17 Feb. 2015, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• HXeI and HXeH in Ar, Kr, and Xe matrices: Experiment and simulation
  Cheng Zhu; Keisuke Niimi; Tetsuya Taketsugu; Masashi Tsuge; Akira Nakayama; Leonid Khriachtchev
  The Journal of Chemical Physics, 142, 5, 054305, 054305, 07 Feb. 2015, [Peer-reviewed], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Systematic Exploration of Minimum Energy Conical Intersection Structures near the Franck–Condon Region
  Satoshi Maeda; Yu Harabuchi; Tetsuya Taketsugu; Keiji Morokuma
  The Journal of Physical Chemistry A, 118, 51, 12050, 12058, 26 Dec. 2014, [Peer-reviewed], [Invited], [International Magazine]
  Scientific journal
• Dynamics Simulations with Spin-Flip Time-Dependent Density Functional Theory: Photoisomerization and Photocyclization Mechanisms of cis-Stilbene in ππ* States
  Yu Harabuchi; Kristopher Keipert; Federico Zahariev; Tetsuya Taketsugu; Mark S. Gordon
  The Journal of Physical Chemistry A, 118, 51, 11987, 11998, 26 Dec. 2014, [Peer-reviewed], [Invited], ［Internationally co-authored］, [International Magazine]
  English, Scientific journal
• Anharmonic Downward Distortion Following for Automated Exploration of Quantum Chemical Potential Energy Surfaces
  Satoshi Maeda; Tetsuya Taketsugu; Keiji Morokuma; Koichi Ohno
  Bulletin of the Chemical Society of Japan, 87, 12, 1315, 1334, 15 Dec. 2014, [Peer-reviewed], [Invited], [Domestic magazines]
  Scientific journal
• Quantum Chemical Investigations on the Nonradiative Deactivation Pathways of Cytosine Derivatives
  Akira Nakayama; Shohei Yamazaki; Tetsuya Taketsugu
  The Journal of Physical Chemistry A, 118, 40, 9429, 9437, 09 Oct. 2014, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal
• Automated Search for Chemical Reaction Pathways by the Artificial Force Induced Reaction Method: Toward Practical Applications in Synthetic Organic Chemistry
  Satoshi Maeda; Miho Hatanaka; Ryohei Uematsu; Tetsuya Taketsugu; Keiji Morokuma
  JOURNAL OF SYNTHETIC ORGANIC CHEMISTRY JAPAN, 72, 5, 567, 579, 16 Jun. 2014, [Peer-reviewed], [Invited], [Domestic magazines]
  Japanese, Scientific journal
• Adsorption and Catalytic Activation of the Molecular Oxygen on the Metal Supported h-BN
  Andrey Lyalin; Akira Nakayama; Kohei Uosaki; Tetsuya Taketsugu
  Topics in Catalysis, 57, 10-13, 1032, 1041, Jun. 2014, [Peer-reviewed], [Invited], [Last author, Corresponding author], [International Magazine]
  English, Scientific journal
• Ultrafast Relaxation Dynamics in trans-1,3-Butadiene Studied by Time-Resolved Photoelectron Spectroscopy with High Harmonic Pulses
  Ayumu Makida; Hironori Igarashi; Takehisa Fujiwara; Taro Sekikawa; Yu Harabuchi; Tetsuya Taketsugu
  The Journal of Physical Chemistry Letters, 5, 10, 1760, 1765, 15 May 2014, [Peer-reviewed], [Last author], [International Magazine]
  English, Scientific journal
• Boron Nitride Nanosheet on Gold as an Electrocatalyst for Oxygen Reduction Reaction: Theoretical Suggestion and Experimental Proof
  Kohei Uosaki; Ganesan Elumalai; Hidenori Noguchi; Takuya Masuda; Andrey Lyalin; Akira Nakayama; Tetsuya Taketsugu
  Journal of the American Chemical Society, 136, 18, 6542, 6545, 07 May 2014, [Peer-reviewed], [Last author], [International Magazine]
  English, Scientific journal
• Catalytic Transfer Hydrogenation by a Trivalent Phosphorus Compound: Phosphorus-Ligand Cooperation Pathway or PIII/PVRedox Pathway?
  Guixiang Zeng; Satoshi Maeda; Tetsuya Taketsugu; Shigeyoshi Sakaki
  Angewandte Chemie International Edition, 126, 18, 4721, 4725, 25 Apr. 2014, [Peer-reviewed], [International Magazine]
  Scientific journal
• Catalytic transfer hydrogenation by a trivalent phosphorus compound: phosphorus-ligand cooperation pathway or P(III) /P(V) redox pathway?
  Zeng Guixiang; Maeda Satoshi; Taketsugu Tetsuya; Sakaki Shigeyoshi
  Angewandte Chemie, 53, 18, 4633, 4637, wiley, 25 Apr. 2014, [Peer-reviewed], [International Magazine]
  English, Main-group-element catalysts are a desirable alternative to transition-metal catalysts because of natural abundance and cost. However, the examples are very limited. Catalytic cycles involving a redox process and E-ligand cooperation (E=main-group element), which are often found in catalytic cycles of transition-metal catalysts, have not been reported. Herein theoretical investigations of a catalytic hydrogenation of azobenzene with ammonia-borane using a trivalent phosphorus compound, which was experimentally proposed to occur through P(III) /P(V) redox processes via an unusual pentavalent dihydridophosphorane, were performed. DFT and ONIOM(CCSD(T):MP2) calculations disclosed that this catalytic reaction occurs through a P-O cooperation mechanism, which resembles the metal-ligand cooperation mechanism of transition-metal catalysts.
• Application of Automated Reaction Path Search Methods to a Systematic Search of Single-Bond Activation Pathways Catalyzed by Small Metal Clusters: A Case Study on H–H Activation by Gold
  Min Gao; Andrey Lyalin; Satoshi Maeda; Tetsuya Taketsugu
  Journal of Chemical Theory and Computation, 10, 4, 1623, 1630, 08 Apr. 2014, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal
• Ab Initio Studies on the Photophysics of Uric Acid and Its Monohydrates: Role of the Water Molecule
  Shohei Yamazaki; Shu-hei Urashima; Hiroyuki Saigusa; Tetsuya Taketsugu
  The Journal of Physical Chemistry A, 118, 6, 1132, 1141, 13 Feb. 2014, [Peer-reviewed], [Last author], [International Magazine]
  Scientific journal
• Direct Pathway for Water–Gas Shift Reaction in Gas Phase
  Yu Harabuchi; Satoshi Maeda; Tetsuya Taketsugu; Koichi Ohno
  Chemistry Letters, 43, 2, 193, 195, 05 Feb. 2014, [Peer-reviewed], [Domestic magazines]
  English, Scientific journal
• Multiple Reaction Pathways Operating in the Mechanism of Vinylogous Mannich-Type Reaction Activated by a Water Molecule
  Ryohei Uematsu; Satoshi Maeda; Tetsuya Taketsugu
  Chemistry - An Asian Journal, 9, 1, 305, 312, Jan. 2014, [Peer-reviewed], [Last author, Corresponding author], [International Magazine]
  Scientific journal
• Exploring Transition State Structures for Intramolecular Pathways by the Artificial Force Induced Reaction Method
  Satoshi Maeda; Tetsuya Taketsugu; Keiji Morokuma
  JOURNAL OF COMPUTATIONAL CHEMISTRY, 35, 2, 166, 173, Jan. 2014, [Peer-reviewed]
  English, Scientific journal
• Vibrational Shifts of HXeCl in Matrix Environments
  Keisuke Niimi; Akira Nakayama; Yuriko Ono; Tetsuya Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY A, 118, 2, 380, 387, Jan. 2014, [Peer-reviewed]
  English, Scientific journal
• Ultrafast and photodissociation dynamics of 1,2-butadiene studied by photoelectron spectroscopy
  Ryo Iikubo; Takehisa Fujiwara; Taro Sekikawa; Yu Harbuchi; Tetsuya Taketsugu
  Optics InfoBase Conference Papers, Optical Society of America (OSA), 2014
  English, International conference proceedings
• Ultrafast relaxation and photodissociation dynamics of 1,3- butadiene studied by Probing molecular orbitals
  A. Makida; T. Fujiwara; Yu Harabuchi; T. Taketsugu; T. Sekikawa
  Optics InfoBase Conference Papers, Optical Society of America (OSA), 2014
  English, International conference proceedings
• 3P081 An extraction of hierarchical organization of embedded timescales buried in complex reaction network(01E. Protein: Measurement & Analysis,Poster,The 52nd Annual Meeting of the Biophysical Society of Japan(BSJ2014))
  Nagahata Yutaka; Maeda Satoshi; Teramoto Hiroshi; Li Chun-Biu; Horiyama Takashi; Taketsugu Tetsuya; Komatsuzaki Tamiki
  Seibutsu Butsuri, 54, 1, S262, The Biophysical Society of Japan General Incorporated Association, 2014
  English
• Solvent effects on the ultrafast nonradiative deactivation mechanisms of thymine in aqueous solution: Excited-state QM/MM molecular dynamics simulations
  Akira Nakayama; Gaku Arai; Shohei Yamazaki; Tetsuya Taketsugu
  JOURNAL OF CHEMICAL PHYSICS, 139, 21, 214304, Dec. 2013, [Peer-reviewed]
  English, Scientific journal
• Exploring Pathways of Photoaddition Reactions by Artificial Force Induced Reaction Method: A Case Study on the Paterno-Buchi Reaction
  Satoshi Maeda; Tetsuya Taketsugu; Keiji Morokuma
  ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS, 227, 9-11, 1421, 1433, Nov. 2013, [Peer-reviewed], [Invited]
  English, Scientific journal
• Functionalization of Monolayer h-BN by a Metal Support for the Oxygen Reduction Reaction
  Andrey Lyalin; Akira Nakayama; Kohei Uosaki; Tetsuya Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY C, 117, 41, 21359, 21370, Oct. 2013, [Peer-reviewed]
  English, Scientific journal
• Automated Search for Minimum Energy Conical Intersection Geometries between the Lowest Two Singlet States S-0/S-1-MECIs by the Spin-Flip TDDFT Method
  Yu Harabuchi; Satoshi Maeda; Tetsuya Taketsugu; Noriyuki Minezawa; Keiji Morokuma
  JOURNAL OF CHEMICAL THEORY AND COMPUTATION, 9, 9, 4116, 4123, Sep. 2013, [Peer-reviewed]
  English, Scientific journal
• Nonprecious-metal-assisted photochemical hydrogen production from ortho-phenylenediamine
  Takeshi Matsumoto; Ho-Chol Chang; Masanori Wakizaka; Sho Ueno; Atsushi Kobayashi; Akira Nakayama; Tetsuya Taketsugu; Masako Kato
  Journal of the American Chemical Society, 135, 23, 8646, 8654, 23, 12 Jun. 2013, [Peer-reviewed]
  English, Scientific journal
• A multireference perturbation study of the NN stretching frequency of trans-azobenzene in nπ* excitation and an implication for the photoisomerization mechanism
  Yu Harabuchi; Moe Ishii; Akira Nakayama; Takeshi Noro; Tetsuya Taketsugu
  Journal of Chemical Physics, 138, 6, 064305, 6, 14 Feb. 2013, [Peer-reviewed]
  English, Scientific journal
• Oxygen activation and dissociation on h-BN supported Au atoms
  Min Gao; Andrey Lyalin; Tetsuya Taketsugu
  INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, 113, 4, 443, 452, Feb. 2013, [Peer-reviewed]
  English, Scientific journal
• CO oxidation on h-BN supported Au atom
  Min Gao; Andrey Lyalin; Tetsuya Taketsugu
  Journal of Chemical Physics, 138, 3, 034701, 3, 21 Jan. 2013, [Peer-reviewed]
  English, Scientific journal
• Theoretical predictions for hexagonal BN based nanomaterials as electrocatalysts for the oxygen reduction reaction
  Andrey Lyalin; Akira Nakayama; Kohei Uosaki; Tetsuya Taketsugu
  PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 15, 8, 2809, 2820, 2013, [Peer-reviewed]
  English, Scientific journal
• Photophysics of cytosine tautomers: new insights into the nonradiative decay mechanisms from MS-CASPT2 potential energy calculations and excited-state molecular dynamics simulations
  Akira Nakayama; Yu Harabuchi; Shohei Yamazaki; Tetsuya Taketsugu
  PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 15, 29, 12322, 12339, 2013, [Peer-reviewed]
  English, Scientific journal
• Crystal structure of ruthenium phthalocyanine with diaxial monoatomic ligand: Bis(triphenylphosphine)iminium dichloro(phthalocyaninato(2-)) ruthenium(III)
  Derrick Ethelbhert Yu; Akira Kikuchi; Tetsuya Taketsugu; Tamotsu Inabe
  Journal of Chemistry, 2013, 486318, 2013, [Peer-reviewed]
  English, Scientific journal
• Exploring Potential Energy Surfaces of Large Systems with Artificial Force Induced Reaction Method in Combination with ONIOM and Microiteration
  Satoshi Maeda; Erika Abe; Miho Hatanaka; Tetsuya Taketsugu; Keiji Morokuma
  JOURNAL OF CHEMICAL THEORY AND COMPUTATION, 8, 12, 5058, 5063, Dec. 2012, [Peer-reviewed], [Invited]
  English, Scientific journal
• Theoretical Study on Water-Mediated Excited-State Multiple Proton Transfer in 7-Azaindole: Significance of Hydrogen Bond Rearrangement
  Xue-fang Yu; Shohei Yamazaki; Tetsuya Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY A, 116, 43, 10566, 10573, Nov. 2012, [Peer-reviewed]
  English, Scientific journal
• Trifurcation of the reaction pathway
  Yu Harabuchi; Akira Nakayama; Tetsuya Taketsugu
  COMPUTATIONAL AND THEORETICAL CHEMISTRY, 1000, 70, 74, Nov. 2012, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of the excited-state double proton transfer in the (3-methyl-7-azaindole)-(7-azaindole) heterodimer
  Xue-Fang Yu; Shohei Yamazaki; Tetsuya Taketsugu
  JOURNAL OF COMPUTATIONAL CHEMISTRY, 33, 20, 1701, 1708, Jul. 2012, [Peer-reviewed]
  English, Scientific journal
• Automated Exploration of Photolytic Channels of HCOOH: Conformational Memory via Excited-State Roaming
  Satoshi Maeda; Tetsuya Taketsugu; Keiji Morokuma
  JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 3, 14, 1900, 1907, Jul. 2012, [Peer-reviewed]
  English, Scientific journal
• Ab initio prediction of vibrational states of the HeCuF helium-containing complex
  Tomokazu Tanaka; Toshiyuki Takayanagi; Tetsuya Taketsugu; Yuriko Ono
  CHEMICAL PHYSICS LETTERS, 539, 15, 18, Jun. 2012, [Peer-reviewed]
  English, Scientific journal
• Catalytic Activity of Au and Au-2 on the h-BN Surface: Adsorption and Activation of O-2
  Min Gao; Andrey Lyalin; Tetsuya Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY C, 116, 16, 9054, 9062, Apr. 2012, [Peer-reviewed]
  English, Scientific journal
• Competing effects of rare gas atoms in matrix isolation spectroscopy: A case study of vibrational shift of BeO in Xe and Ar matrices
  Akira Nakayama; Keisuke Niimi; Yuriko Ono; Tetsuya Taketsugu
  JOURNAL OF CHEMICAL PHYSICS, 136, 5, 054506, Feb. 2012, [Peer-reviewed]
  English, Scientific journal
• Ab Initio Molecular Dynamics Approach to Tunneling Splitting in Polyatomic Molecules
  Yusuke Ootani; Tetsuya Taketsugu
  JOURNAL OF COMPUTATIONAL CHEMISTRY, 33, 1, 60, 65, Jan. 2012, [Peer-reviewed]
  English, Scientific journal
• Nonradiative Deactivation Mechanisms of Uracil, Thymine, and 5-Fluorouracil: A Comparative ab Initio Study
  Shohei Yamazaki; Tetsuya Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY A, 116, 1, 491, 503, Jan. 2012, [Peer-reviewed]
  English, Scientific journal
• Femtosecond fluorescence study of the reaction pathways and nature of the reactive S-1 state of cis-stilbene
  Takumi Nakamura; Satoshi Takeuchi; Tetsuya Taketsugu; Tahei Tahara
  PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 14, 18, 6225, 6232, 2012, [Peer-reviewed]
  English, Scientific journal
• Photoreaction channels of the guanine-cytosine base pair explored by long-range corrected TDDFT calculations
  Shohei Yamazaki; Tetsuya Taketsugu
  PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 14, 25, 8866, 8877, 2012, [Peer-reviewed]
  English, Scientific journal
• Role of the Support Effects on the Catalytic Activity of Gold Clusters: A Density Functional Theory Study
  Min Gao; Andrey Lyalin; Tetsuya Taketsugu
  CATALYSTS, 1, 1, 18, 39, Dec. 2011, [Peer-reviewed], [Invited]
  English, Scientific journal
• A significant role of the totally symmetric valley-ridge inflection point in the bifurcating reaction pathway
  Yu Harabuchi; Tetsuya Taketsugu
  THEORETICAL CHEMISTRY ACCOUNTS, 130, 2-3, 305, 315, Oct. 2011, [Peer-reviewed], [Invited]
  English, Scientific journal
• Ultrafast Nonradiative Decay of Electronically Excited States of Malachite Green: Ab Initio Calculations
  Akira Nakayama; Tetsuya Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY A, 115, 32, 8808, 8815, Aug. 2011, [Peer-reviewed]
  English, Scientific journal
• Ab Initio Molecular Dynamics Study of H-2 Formation Inside POSS Compounds
  Takako Kudo; Tetsuya Taketsugu; Mark S. Gordon
  JOURNAL OF PHYSICAL CHEMISTRY A, 115, 13, 2679, 2691, Apr. 2011, [Peer-reviewed]
  English, Scientific journal
• Thermal Decomposition of 2-Butanol as a Potential Nonfossil Fuel: A Computational Study
  Ahmed M. El-Nahas; Ahmed H. Mangood; Hikaru Takeuchi; Tetsuya Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY A, 115, 13, 2837, 2846, Apr. 2011, [Peer-reviewed]
  English, Scientific journal
• Concerted or Stepwise Mechanism? CASPT2 and LC-TDDFT Study of the Excited-State Double Proton Transfer in the 7-Azaindole Dimer
  Xue-fang Yu; Shohei Yamazaki; Tetsuya Taketsugu
  JOURNAL OF CHEMICAL THEORY AND COMPUTATION, 7, 4, 1006, 1015, Apr. 2011, [Peer-reviewed]
  English, Scientific journal
• A computational investigation of H-2 adsorption and dissociation on Au nanoparticles supported on TiO2 surface
  Andrey Lyalin; Tetsuya Taketsugu
  FARADAY DISCUSSIONS, 152, 185, 201, 2011, [Peer-reviewed], [Invited]
  English, Scientific journal
• Reactant-Promoted Oxygen Dissociation on Gold Clusters
  Andrey Lyalin; Tetsuya Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY LETTERS, 1, 12, 1752, 1757, Jun. 2010, [Peer-reviewed]
  English, Scientific journal
• Formation of a Pd atomic chain in a hydrogen atmosphere
  Manabu Kiguchi; Kunio Hashimoto; Yuriko Ono; Tetsuya Taketsugu; Kei Murakoshi
  PHYSICAL REVIEW B, 81, 19, 195401, May 2010, [Peer-reviewed]
  English, Scientific journal
• Ab Initio Study of Xe Adsorption on Graphene
  Li Sheng; Yuriko Ono; Tetsuya Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY C, 114, 8, 3544, 3548, Mar. 2010, [Peer-reviewed]
  English, Scientific journal
• Adsorption of Ethylene on Neutral, Anionic, and Cationic Gold Clusters
  Andrey Lyalin; Tetsuya Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY C, 114, 6, 2484, 2493, Feb. 2010, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of Ar-MCO (M = Pd, Pt)
  Yuriko Taketsugu; Takeshi Noro; Tetsuya Taketsugu
  CHEMICAL PHYSICS LETTERS, 484, 4-6, 139, 143, Jan. 2010, [Peer-reviewed]
  English, Scientific journal
• Ab initio molecular dynamics simulation of photoisomerization in azobenzene in the n pi(*) state
  Yusuke Ootani; Kiminori Satoh; Akira Nakayama; Takeshi Noro; Tetsuya Taketsugu
  JOURNAL OF CHEMICAL PHYSICS, 131, 19, 194306, Nov. 2009, [Peer-reviewed]
  English, Scientific journal
• Speed-up of Ab Initio Hybrid Monte Carlo and Ab Initio Path Integral Hybrid Monte Carlo Simulations by Using an Auxiliary Potential Energy Surface
  Akira Nakayama; Tetsuya Taketsugu; Motoyuki Shiga
  CHEMISTRY LETTERS, 38, 10, 976, 977, Oct. 2009, [Peer-reviewed]
  English, Scientific journal
• Ab Initio QM/MM Excited-State Molecular Dynamics Study of Coumarin 151 in Water Solution
  Daisuke Kina; Pooja Arora; Akira Nakayama; Takeshi Noro; Mark S. Gordon; Tetsuya Taketsugu
  INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, 109, 10, 2308, 2318, Aug. 2009, [Peer-reviewed], [Invited]
  English, Scientific journal
• Cooperative Adsorption of O-2 and C2H4 on Small Gold Clusters
  Andrey Lyalin; Tetsuya Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY C, 113, 30, 12930, 12934, Jul. 2009, [Peer-reviewed]
  English, Scientific journal
• Nonequilibrium Green's function study on the electronic structure and transportation behavior of the conjugated molecular junction: Terminal connections and intramolecular connections
  Hongmei Liu; Wenbin Ni; Jianwei Zhao; Nan Wang; Yan Guo; Tetsuya Taketsugu; Manabu Kiguchi; Kei Murakoshi
  JOURNAL OF CHEMICAL PHYSICS, 130, 24, 244501, Jun. 2009, [Peer-reviewed]
  English, Scientific journal
• Efficient sampling for ab initio Monte Carlo simulation of molecular clusters using an interpolated potential energy surface
  Akira Nakayama; Nanami Seki; Tetsuya Taketsugu
  JOURNAL OF CHEMICAL PHYSICS, 130, 2, 024107, Jan. 2009, [Peer-reviewed]
  English, Scientific journal
• Variable magnetotransport properties in the TPP[Fe(Pc)L-2](2) system (TPP = tetraphenylphosphonium, Pc = phthalocyaninato, L = CN, Cl, and Br)
  Derrick Ethelbhert C. Yu; Masaki Matsuda; Hiroyuki Tajima; Akira Kikuchi; Tetsuya Taketsugu; Noriaki Hanasaki; Toshio Naito; Tamotsu Inabe
  JOURNAL OF MATERIALS CHEMISTRY, 19, 6, 718, 723, 2009, [Peer-reviewed]
  English, Scientific journal
• Path-integral molecular dynamics simulations of BeO embedded in helium clusters: Formation of the stable HeBeO complex
  Haruki Motegi; Akira Kakizaki; Toshiyuki Takayanagi; Yuriko Taketsugu; Tetsuya Takesugu; Motyuki Shiga
  CHEMICAL PHYSICS, 354, 1-3, 38, 43, Dec. 2008, [Peer-reviewed]
  English, Scientific journal
• Spectroscopic Tracking of Structural Evolution in Ultrafast Stilbene Photoisomerization
  Satoshi Takeuchi; Sanford Ruhman; Takao Tsuneda; Mahito Chiba; Tetsuya Taketsugu; Tahei Tahara
  SCIENCE, 322, 5904, 1073, 1077, Nov. 2008, [Peer-reviewed]
  English, Scientific journal
• Ab initio QM/MM molecular dynamics study on the excited-state hydrogen transfer of 7-azaindole in water solution
  Daisuke Kina; Akira Nakayama; Takeshi Noro; Tetsuya Taketsugu; Mark S. Gordon
  JOURNAL OF PHYSICAL CHEMISTRY A, 112, 40, 9675, 9683, Oct. 2008, [Peer-reviewed]
  English, Scientific journal
• An ab initio molecular dynamics study on the dissociative recombination reaction of HD(2)O(+)+e(-)
  Megumi Kayanuma; Tetsuya Taketsugu; Keisaku Ishii
  THEORETICAL CHEMISTRY ACCOUNTS, 120, 1-3, 191, 198, May 2008, [Peer-reviewed], [Invited]
  English, Scientific journal
• Accurate ab initio electronic structure calculations of the stable helium complex: HeBeO
  Toshiyuki Takayanagi; Haruki Motegi; Yuriko Taketsugu; Tetsuya Taketsugu
  CHEMICAL PHYSICS LETTERS, 454, 1-3, 1, 6, Mar. 2008, [Peer-reviewed]
  English, Scientific journal
• Identification of the matrix shift: A fingerprint for neutral neon complex?
  Yuriko Taketsugu; Takeshi Noro; Tetsuya Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY A, 112, 5, 1018, 1023, Feb. 2008, [Peer-reviewed]
  English, Scientific journal
• Ab initio study of KN
  Keisaku Ishii; Tetsuya Taketsugu; Koichi Yamashita
  JOURNAL OF CHEMICAL PHYSICS, 127, 19, 194307, Nov. 2007, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of the simplest Xe-containing molecule: HXeH
  Toshiyuki Takayanagi; Tomoko Asakura; Kenta Takahashi; Yuriko Taketsugu; Tetsuya Taketsugu; Takeshi Noro
  CHEMICAL PHYSICS LETTERS, 446, 1-3, 14, 19, Sep. 2007, [Peer-reviewed]
  English, Scientific journal
• Fermi resonance in CO2: A combined electronic coupled-cluster and vibrational configuration-interaction prediction
  Valerie Rodriguez-Garcia; So Hirata; Kiyoshi Yagi; Kimihiko Hirao; Tetsuya Taketsugu; Igor Schweigert; Mitsuo Tasumi
  JOURNAL OF CHEMICAL PHYSICS, 126, 12, 124303, Mar. 2007, [Peer-reviewed]
  English, Scientific journal
• Theoretical prediction of noble-gas compounds: Ng-Pd-Ng and Ng-Pt-Ng
  Yuriko Taketsugu; Tetsuya Taketsugu; Takeshi Noro
  JOURNAL OF CHEMICAL PHYSICS, 125, 15, 154308, Oct. 2006, [Peer-reviewed]
  English, Scientific journal
• Ab initio prediction of the spectroscopic constants of NaN: Another potential candidate for a new Na-bearing interstellar molecule
  Keisaku Ishii; Tetsuya Taketsugu; Koichi Yamashita
  CHEMICAL PHYSICS LETTERS, 427, 1-3, 1, 4, Aug. 2006, [Peer-reviewed]
  English, Scientific journal
• Highly accurate potential-energy and dipole moment surfaces for vibrational state calculations of methane
  C Oyanagi; K Yagi; T Taketsugu; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 124, 6, 64311, Feb. 2006, [Peer-reviewed]
  English, Scientific journal
• Ab initio surface hopping simulation on dissociative recombination of H3O+
  M Kayanuma; T Taketsugu; K Ishii
  CHEMICAL PHYSICS LETTERS, 418, 4-6, 511, 518, Feb. 2006, [Peer-reviewed]
  English, Scientific journal
• Theoretical elucidation of the unusually high [HNC]/[HCN] abundance ratio in interstellar space: Two-dimensional and two-state quantum wave packet dynamics study on the branching ratio of the dissociative recombination reaction HCNH++E- -> HNC/HCN+H
  K Ishii; A Tajima; T Taketsugu; K Yamashita
  ASTROPHYSICAL JOURNAL, 636, 2, 927, 931, Jan. 2006, [Peer-reviewed]
  English, Scientific journal
• Reduced-dimensionality and direct trajectory calculations for the C((3) P-J)+NH2 (B-2(1)) reaction
  T Takayanagi; T Taketsugu
  CHEMICAL PHYSICS LETTERS, 417, 1-3, 143, 148, Jan. 2006, [Peer-reviewed]
  English, Scientific journal
• Ab initio prediction of spectroscopic constants of can in the lowest (2)Pi, (4)Sigma(-), (2)Sigma(-), and (4)Pi electronic states: A potential candidate for the first calcium-bearing interstellar molecule
  K Ishii; T Taketsugu
  ASTROPHYSICAL JOURNAL, 634, 2, L201, L204, Dec. 2005, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of Pt-Ng and Ng-Pt-Ng (Ng=Ar,Kr,Xe)
  Y Ono; T Taketsugu; T Noro
  JOURNAL OF CHEMICAL PHYSICS, 123, 20, 204321, Nov. 2005, [Peer-reviewed]
  English, Scientific journal
• A vibrational analysis of the 7-azaindole-water complex: Anharmonicities using the quartic force field
  T Taketsugu; K Yagi; MS Gordon
  INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, 104, 5, 758, 772, Sep. 2005, [Peer-reviewed], [Invited]
  English, Scientific journal
• An ab initio study of tunneling splittings in the water trimer
  M Takahashi; Y Watanabe; T Taketsugu; DJ Wales
  JOURNAL OF CHEMICAL PHYSICS, 123, 4, 044302, Jul. 2005, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of chemical binding of noble gas atom and transition metal complexes: Ng-NiCO, Ng-NiN2, Ng-CoCO (Ng = He-Xe)
  Y Ono; T Taketsugu
  MONATSHEFTE FUR CHEMIE, 136, 6, 1087, 1106, Jun. 2005, [Peer-reviewed]
  English, Scientific journal
• Ab initio prediction of spectroscopic constants of MgN in X-4 Sigma(-) and a(2)Pi electronic states: Another potential candidate for a new Mg-bearing interstellar molecule
  K Ishii; T Taketsugu
  ASTROPHYSICAL JOURNAL, 626, 1, L33, L35, Jun. 2005, [Peer-reviewed]
  English, Scientific journal
• Development of a three-dimensional ab initio potential energy surface for the He-Cl-2(X) system and its application to solvation structures in the HenCl2 clusters
  T Takayanagi; M Shiga; T Taketsugu
  JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY, 4, 1, 197, 207, Mar. 2005, [Peer-reviewed], [Invited]
  English, Scientific journal
• Effect of out-of-plane vibration on the hydrogen atom transfer reaction in malonaldehyde
  K Yagi; GV Mil'nikov; T Taketsugu; K Hirao; H Nakamura
  CHEMICAL PHYSICS LETTERS, 397, 4-6, 435, 440, Oct. 2004, [Peer-reviewed]
  English, Scientific journal
• The effect of fluorination: A crystallographic and computational study of mesogenic alkyl 4-[2-(perfluorooctyl)ethoxy]benzoates
  M Yano; T Taketsuga; K Hori; H Okamoto; S Takenaka
  CHEMISTRY-A EUROPEAN JOURNAL, 10, 16, 3991, 3999, Aug. 2004, [Peer-reviewed]
  English, Scientific journal
• Ab initio vibrational state calculations with a quartic force field: Applications to H2CO, C2H4, CH3OH, CH3CCH, and C6H6
  K Yagi; K Hirao; T Taketsugu; MW Schmidt; MS Gordon
  JOURNAL OF CHEMICAL PHYSICS, 121, 3, 1383, 1389, Jul. 2004, [Peer-reviewed]
  English, Scientific journal
• The effect of spin-orbit coupling on fast neutral chemical reaction O(P-3)+CH3 -> CH3O
  K Yagi; T Takayanagi; T Taketsugu; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 120, 22, 10395, 10403, Jun. 2004, [Peer-reviewed]
  English, Scientific journal
• Ab initio direct trajectory simulation with nonadiabatic transitions of the dissociative recombination reaction HCNH+ plus e(-) -> HNC/HCN plus H
  T Taketsugu; A Tajima; K Ishii; T Hirano
  ASTROPHYSICAL JOURNAL, 608, 1, 323, 329, Jun. 2004, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of Ar-CoCO
  Y Ono; T Taketsugu
  JOURNAL OF PHYSICAL CHEMISTRY A, 108, 25, 5464, 5467, Jun. 2004, [Peer-reviewed]
  English, Scientific journal
• An ab initio study of tunneling splittings in the water dimer
  Y Watanabe; T Taketsugufoot; DJ Wales
  JOURNAL OF CHEMICAL PHYSICS, 120, 13, 5993, 5999, Apr. 2004, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of Ng-NiN2 (Ng=Ar,Ne,He)
  Y Ono; T Taketsugu
  JOURNAL OF CHEMICAL PHYSICS, 120, 13, 6035, 6040, Apr. 2004, [Peer-reviewed]
  English, Scientific journal
• Simple and accurate method to evaluate tunneling splitting in polyatomic molecules
  GV Mil'nikova; K Yagi; T Taketsugu; H Nakamura; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 120, 11, 5036, 5045, Mar. 2004, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of Ng-NiCO (Ng = Ar, Ne, He)
  Y Ono; T Taketsugu
  CHEMICAL PHYSICS LETTERS, 385, 1-2, 85, 91, Feb. 2004, [Peer-reviewed]
  English, Scientific journal
• Kinetic measurements for the reactions of ozone with crotonaldehyde and its methyl derivatives and calculations of transition-state theory
  K Sato; B Klotz; T Taketsugu; T Takayanagi
  PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 6, 15, 3969, 3976, 2004, [Peer-reviewed]
  English, Scientific journal
• Theoretical determination of the spin-rovibronic spectrum of the (A)over-tilde(2)Pi <-(X)over-tilde(2)Sigma(+) electronic transition of MgNC
  T Taketsugu; K Ishii; S Carter
  CHEMICAL PHYSICS LETTERS, 380, 1-2, 213, 222, Oct. 2003, [Peer-reviewed]
  English, Scientific journal
• Tunneling splitting in polyatomic molecules: Application to malonaldehyde
  GV Mil'nikov; K Yagi; T Taketsugu; H Nakamura; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 119, 1, 10, 13, Jul. 2003, [Peer-reviewed]
  English, Scientific journal
• Theoretical study on the potential energy surfaces of CaNC and CaCN
  K Ishii; T Taketsugu; T Hirano
  CHEMICAL PHYSICS LETTERS, 374, 5-6, 506, 512, Jun. 2003, [Peer-reviewed]
  English, Scientific journal
• Ab initio potential energy surface for vibrational state calculations of H2CO
  K Yagi; C Oyanagi; T Taketsugu; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 118, 4, 1653, 1660, Jan. 2003, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of rearrangements in water dimer and trimer
  T Taketsugu; DJ Wales
  MOLECULAR PHYSICS, 100, 17, 2793, 2806, Sep. 2002, [Peer-reviewed]
  English, Scientific journal
• Direct trajectory simulation on the growth of carbon nanotubes
  Y Kumeda; T Taketsugu; T Hirano
  CHEMICAL PHYSICS LETTERS, 360, 1-2, 149, 154, Jul. 2002, [Peer-reviewed]
  English, Scientific journal
• A new analytic form of ab initio potential energy function: An application to H2O
  K Yagi; T Taketsugu; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 116, 10, 3963, 3966, Mar. 2002, [Peer-reviewed]
  English, Scientific journal
• Multireference perturbation study of ClF+4
  T Taketsugu; DJ Wales
  PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 4, 10, 1722, 1724, 2002, [Peer-reviewed]
  English, Scientific journal
• Ab initio study of the ground and two low-lying electronic excited states of FeC
  SS Itono; T Taketsugu; T Hirano; U Nagashima
  JOURNAL OF CHEMICAL PHYSICS, 115, 24, 11213, 11220, Dec. 2001, [Peer-reviewed]
  English, Scientific journal
• Generation of full-dimensional potential energy surface of intramolecular hydrogen atom transfer in malonaldehyde and tunneling dynamics
  K Yagi; T Taketsugu; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 115, 23, 10647, 10655, Dec. 2001, [Peer-reviewed]
  English, Scientific journal
• Ab initio molecular orbital prediction of the Renner-Teller effect for the first excited state (2)Pi of MgNC: Reinterpretation of the laser-induced fluorescence spectrum based on the predicted spectroscopic constants
  TE Odaka; T Taketsugu; T Hirano; U Nagashima
  JOURNAL OF CHEMICAL PHYSICS, 115, 3, 1349, 1354, Jul. 2001, [Peer-reviewed]
  English, Scientific journal
• A variational determination of spin-rovibronic energy levels of MgNC in the A(2)Pi state
  T Taketsugu; S Carter
  CHEMICAL PHYSICS LETTERS, 340, 3-4, 385, 389, Jun. 2001, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of first-row transition metal oxide cations
  Y Nakao; K Hirao; T Taketsugu
  JOURNAL OF CHEMICAL PHYSICS, 114, 18, 7935, 7940, May 2001, [Peer-reviewed]
  English, Scientific journal
• An ab initio direct-trajectory study of the kinetic isotope effect on the bifurcating reaction
  T Taketsugu; Y Kumeda
  JOURNAL OF CHEMICAL PHYSICS, 114, 16, 6973, 6982, Apr. 2001, [Peer-reviewed]
  English, Scientific journal
• Stability of multiply charged anions of lanthanide hexafluorides LnF(6)(2-) and LnF(6)(3-) (Ln = Ce to Lu)
  K Takeda; T Tsuchiya; H Nakano; T Taketsugu; K Hirao
  JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM, 537, 107, 115, Mar. 2001, [Peer-reviewed], [Invited]
  English, Scientific journal
• Theoretical study of the water activation by a cobalt cation: Ab initio multireference theory versus density functional theory
  Y Nakao; K Hirao; T Taketsugu
  JOURNAL OF CHEMICAL PHYSICS, 114, 12, 5216, 5223, Mar. 2001, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of nanotube growth in terms of frontier density distribution
  Y Kumeda; Y Fukuhiro; T Taketsugu; T Hirano
  CHEMICAL PHYSICS LETTERS, 333, 1-2, 29, 35, Jan. 2001, [Peer-reviewed]
  English, Scientific journal
• Isotope effect on bifurcating reaction path: Valley-ridge inflection point in totally symmetric coordinate
  Y Kumeda; T Taketsugu
  JOURNAL OF CHEMICAL PHYSICS, 113, 2, 477, 484, Jul. 2000, [Peer-reviewed]
  English, Scientific journal
• Direct vibrational self-consistent field method: Applications to H2O and H2CO
  K Yagi; T Taketsugu; K Hirao; MS Gordon
  JOURNAL OF CHEMICAL PHYSICS, 113, 3, 1005, 1017, Jul. 2000, [Peer-reviewed]
  English, Scientific journal
• Multidimensional tunneling dynamics on HSiOH cis-trans isomerization using ab initio potential energy surface
  T Taketsugu; N Watanabe; K Hirao
  PROGRESS OF THEORETICAL PHYSICS SUPPLEMENT, 138, 135, 136, 2000, [Peer-reviewed], [Invited]
  English, Scientific journal
• Multidimensional tunneling dynamics on HSiOH cis-trans isomerization with interpolated potential energy surface
  T Taketsugu; N Watanabe; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 111, 8, 3410, 3419, Aug. 1999, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of ammonia activation by M(+) (M=Sc, Ni, Cu)
  Y Nakao; T Taketsugu; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 110, 22, 10863, 10873, Jun. 1999, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of electronic and geometric structures of a series of lanthanide trihalides LnX(3) (Ln = La-Lu ; X = Cl, F)
  T Tsuchiya; T Taketsugu; H Nakano; K Hirao
  JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM, 461, 203, 222, Apr. 1999, [Peer-reviewed], [Invited]
  English, Scientific journal
• Ab initio molecular orbital dynamic reaction path simulations of HNC reversible arrow HCN isomerization reaction: election of the reaction mode in a thermally excited system
  Y Kumeda; Y Minami; K Takano; T Taketsugu; T Hirano
  JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM, 458, 3, 285, 291, Jan. 1999, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of CH4 photodissociation on Pd and Ni(111) surfaces
  Y Akinaga; T Taketsugu; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 109, 24, 11010, 11017, Dec. 1998, [Peer-reviewed]
  English, Scientific journal
• Dynamic reaction path study of SiH4+F--> SiH4F- and the Berry pseudorotation with valley-ridge inflection
  T Taketsugu; T Yanai; K Hirao; MS Gordon
  THEOCHEM-JOURNAL OF MOLECULAR STRUCTURE, 451, 1-2, 163, 177, Sep. 1998, [Peer-reviewed], [Invited]
  English, Scientific journal
• Ab initio potential energy surface by modified Shepard interpolation: Application to the CH3+H-2 -> CH4+H reaction
  Takata, I; T Taketsugu; K Hirao; MS Gordon
  JOURNAL OF CHEMICAL PHYSICS, 109, 11, 4281, 4289, Sep. 1998, [Peer-reviewed]
  English, Scientific journal
• A least-action variational method for determining tunneling paths in multidimensional system
  T Taketsugu; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 107, 24, 10506, 10514, Dec. 1997, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of bifurcating reaction paths
  T Yanai; T Taketsugu; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 107, 4, 1137, 1146, Jul. 1997, [Peer-reviewed]
  English, Scientific journal
• Theoretical study of CH4 photodissociation on the Pt(111) surface
  Y Akinaga; T Taketsugu; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 107, 2, 415, 424, Jul. 1997, [Peer-reviewed]
  English, Scientific journal
• Theoretical study on adsorption and proton exchange reaction of H2O on H-form zeolite
  N Tajima; T Taketsugu; K Hirao
  CHEMICAL PHYSICS, 218, 3, 257, 265, Jun. 1997, [Peer-reviewed]
  English, Scientific journal
• An ab initio study of the reaction mechanism of Co++NH3
  T Taketsugu; MS Gordon
  JOURNAL OF CHEMICAL PHYSICS, 106, 20, 8504, 8515, May 1997, [Peer-reviewed]
  English
• Approaches to bifurcating reaction path
  T Taketsugu; N Tajima; K Hirao
  JOURNAL OF CHEMICAL PHYSICS, 105, 5, 1933, 1939, Aug. 1996, [Peer-reviewed]
  English, Scientific journal
• Interfacing electronic structure theory with dynamics
  Mark S. Gordon; Galina Chaban; Tetsuya Taketsugu
  The Journal of Physical Chemistry, 100, 11512, 11525, Jun. 1996, [Peer-reviewed]
• Perturbation theory and dynamic reaction path analysis of intramolecular vibration mixing: An application to the case of H2O
  T Taketsugu; T Hirano
  JOURNAL OF CHEMICAL PHYSICS, 104, 16, 6081, 6088, Apr. 1996, [Peer-reviewed]
  English, Scientific journal
• Reaction path Hamiltonian based on a reaction coordinate and a curvature coordinate
  T Taketsugu; MS Gordon
  JOURNAL OF CHEMICAL PHYSICS, 104, 8, 2834, 2840, Feb. 1996, [Peer-reviewed]
  English, Scientific journal
• DYNAMIC REACTION-PATH ANALYSIS BASED ON AN INTRINSIC REACTION COORDINATE
  T TAKETSUGU; MS GORDON
  JOURNAL OF CHEMICAL PHYSICS, 103, 23, 10042, 10049, Dec. 1995, [Peer-reviewed]
  English, Scientific journal
• Dynamic reaction path study of SiH4 + H- → SiH5- and the Berry pseudorotation mechanism
  Tetsuya Taketsugu; Mark S. Gordon
  Journal of Physical Chemistry, 99, 14597, 14604, Sep. 1995, [Peer-reviewed]
• DYNAMIC REACTION COORDINATE ANALYSIS - AN APPLICATION TO SIH4+H--]SIH5-
  T TAKETSUGU; MS GORDON
  JOURNAL OF PHYSICAL CHEMISTRY, 99, 21, 8462, 8471, May 1995, [Peer-reviewed]
  English, Scientific journal
• STABILITY OF SMALL FULLERENES C-N (N=36, 40 AND 60) - A TOPOLOGICAL AND MOLECULAR-ORBITAL APPROACH
  K NASU; T TAKETSUGU; T NAKANO; U NAGASHIMA; H HOSOYA
  THEORETICA CHIMICA ACTA, 90, 2-3, 75, 86, Jan. 1995, [Peer-reviewed]
  English, Scientific journal
• POSSIBILITY OF VIBRATIONAL-EXCITATION BY A UNIFORM ELECTRIC-FIELD
  T TAKETSUGU; T HIRANO
  JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM, 115, 1, 37, 44, May 1994, [Peer-reviewed]
  English, Scientific journal
• A NEW-TYPE CUSP FOR THE SOMO AND 2ND-HOMO INTERCHANGING TRANSITION-STATE - A CASE FOUND FOR THE ADSORPTION PROCESS OF DIMETHYLZINC ONTO THE SE4ZN4 CATION CLUSTER
  T NAKANO; T TAKETSUGU; T HIRANO
  JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM, 111, 111, 115, Mar. 1994, [Peer-reviewed]
  English, Scientific journal
• Bifurcation analysis in terms of second-order Jahn-Teller effect
  Tetsuya Taketsugu; Tsuneo Hirano
  Journal of Molecular Structure: THEOCHEM, 310, 169, 176, 1994, [Peer-reviewed], [Invited]
  English, Scientific journal
• Vibration mixing: An application to the prediction of the transition normal vibration mode
  Tsuneo Hirano; Tetsuya Taketsugu; Yasuyuki Kurita
  Journal of Physical Chemistry, 98, 28, 6942, 6949, 1994, [Peer-reviewed]
  English, Scientific journal
• Vibration mixing in terms of normal modes
  Tsuneo Hirano; Tetsuya Taketsugu; Yasuyuki Kurita
  Journal of Physical Chemistry, 98, 28, 6936, 6941, 1994, [Peer-reviewed]
  English, Scientific journal
• MECHANISM OF BIFURCATION ALONG THE REACTION-PATH - AN APPLICATION IN THE CASE OF THIOFORMALDEHYDE
  T TAKETSUGU; T HIRANO
  JOURNAL OF CHEMICAL PHYSICS, 99, 12, 9806, 9814, Dec. 1993, [Peer-reviewed]
  English, Scientific journal

• Low-Dimensional Projection of Reactive Islands in Chemical Reaction Dynamics Using a Supervised Dimensionality Reduction Method
  Ryoichi Tanaka; Yuta Mizuno; Takuro Tsutsumi; Mikito Toda; Tetsuya Taketsugu; Tamiki Komatsuzaki, arXiv, Mar. 2024
  Transition state theory is a standard framework for predicting the rate of a chemical reaction. Although the transition state theory has been successfully applied to numerous chemical reaction analyses, many experimental and theoretical studies have reported chemical reactions with a reactivity which cannot be explained by the transition state theory due to dynamic effects. Dynamical systems theory provides a theoretical framework for elucidating dynamical mechanisms of such chemical reactions. In particular, reactive islands are essential phase space structures revealing dynamical reaction patterns. However, the numerical computation of reactive islands in a reaction system of many degrees of freedom involves an intrinsic challenge—the curse of dimensionality. In this paper, we propose a dimensionality reduction algorithm for computing reactive islands in a reaction system of many degrees of freedom. Using the supervised principal component analysis, the proposed algorithm projects reactive islands into a low-dimensional phase space with preserving the dynamical information on reactivity as much as possible. The effectiveness of the proposed algorithm is examined by numerical experiments for Hénon-Heiles systems extended to many degrees of freedom. The numerical results indicate that our proposed algorithm is effective in terms of the quality of reactivity prediction and the clearness of the boundaries of projected reactive islands. The proposed algorithm is a promising elemental technology for practical applications of dynamical systems analysis to real chemical systems., English, Technical report
• 反応経路自動探索法を活用した合理的メタン燃焼触媒開発
  安村駿作; 斉田謙一郎; 鳥屋尾隆; 武次徹也; 武次徹也; 清水研一, 触媒討論会予稿集(CD-ROM), 133rd, 2024
• Development of X-ray Activatable Caged Compounds Using Azo Bond Cleavage
  小河原浩輝; 家田直弥; 中島孝平; 高倉栄男; 斉田謙一郎; KUMAR Sonu; KUMAR Sonu; 小林正人; 武次徹也; 武次徹也; 稲波修; 小川美香子; 小川美香子, 日本薬学会年会要旨集(Web), 144th, 2024
• テトラキス型キラルEu(III)錯体のπ-4f電荷移動励起状態に基づくキラル光学特性
  滝沢諒平; 富川虎乃輔; 板谷康佑; 中井拓真; ワン メンフィ; ワン メンフィ; 小林正人; 小林正人; 武次徹也; 武次徹也; 長谷川靖哉; 長谷川靖哉; 北川裕一; 北川裕一, 配位化合物の光化学討論会講演要旨集, 35th, 2024
• Thermodynamic and kinetic analyses of oxygen evolution reaction based on the machine-learning analysis and quantum chemical calculations.
  福島知宏; 深澤元貴; WANG Ben; LYALIN Andrey; 武次徹也; 武次徹也; 村越敬, 電気化学会大会講演要旨集(Web), 90th, 2023
• ヘキサフルオロアセチルアセトナートを有するセリウム錯体の電荷移動発光
  富川虎乃輔; ワン メンフィ; 庄司淳; 赤間知子; 小林正人; 小林正人; 伏見公志; 中西貴之; 武次徹也; 武次徹也; 長谷川靖哉; 長谷川靖哉; 北川裕一; 北川裕一, 配位化合物の光化学討論会講演要旨集, 34th, 2023
• 量子アニーリング計算と機械学習を用いた高精度量子化学計算法の開発
  米山亮; 能條小夜子; 小林正人; 小林正人; 武次徹也; 武次徹也, 化学系学協会北海道支部冬季研究発表会(Web), 2023, 2023
• Development of X-ray activated caged compounds by using azo bond cleavage
  小河原浩輝; 高倉栄男; 中島孝平; 斉田謙一郎; KUMAR Sonu; 小林正人; 武次徹也; 稲浪修; 小川美香子, 日本癌学会学術総会抄録集(Web), 82nd, 2023
• Creation of descriptors for potential energy surface using reaction route map and persistent homology
  村山武来; 小林正人; 小林正人; 青木雅允; 石橋卓; 齋藤琢弥; 中村壮伸; 寺本央; 武次徹也; 武次徹也, 分子科学討論会講演プログラム&要旨(Web), 17th, 2023
• Charge transfer emission of Ce(III) complexes with β-diketonate ligands
  富川虎乃輔; 庄司淳; 庄司淳; 赤間知子; 小林正人; 小林正人; 伏見公志; 中西貴之; 武次徹也; 武次徹也; 長谷川靖哉; 長谷川靖哉; 北川裕一; 北川裕一, 希土類, 82, 2023
• Molecular Recognition and Luminescent Properties of Supramolecular Cage Organized by Porphyrin and Yb(III) Complex
  庄司淳; 細谷祥太; 中西貴之; 小林正人; 小林正人; 伏見公志; 北川裕一; 北川裕一; 武次徹也; 武次徹也; 長谷川靖哉; 長谷川靖哉, 基礎有機化学討論会要旨集, 33rd (CD-ROM), 2023
• Theoretical study on the photochemical reaction of naphthalene with carbon tetrachloride
  中澤伸太; 斉田謙一郎; 渡辺昭敬; 武次徹也; 武次徹也, 分子科学討論会講演プログラム&要旨(Web), 16th, 2022
• イジング計算機とfactorization machineを用いた「望みのプロパティ」を持つ化合物の提案
  米山亮; 田代啓介; 小林正人; 小林正人; 武次徹也; 武次徹也, 化学系学協会北海道支部冬季研究発表会(Web), 2022, 2022
• Front cover
  Takuro Tsutsumi; Yuriko Ono; Tetsuya Taketsugu, Chemical Communications, 57, 89, 11723, 11723, 09 Nov. 2021, [Invited]
  Royal Society of Chemistry (RSC)
• Natural reaction orbitals
  Suichi Ebisawa; Msatoshi Hasebe; Takuro Tsutsumi; Takao Tsuneda; Tetsuya Taketsugu, Chemrxiv, 16 Aug. 2021, [International Magazine]
  Natural reaction orbital (NRO) for analyzing chemical reactions from the viewpoint of the electronic theory is presented. The pair of the occupied and virtual NROs that drives chemical reaction are automatically extracted from the solutions of the coupled-perturbed self-consistent-field (CPSCF) equation for the perturbation of the nuclear displacement along the reaction path. Applying the NRO-based reaction analysis method to the H2CO– + H3CCl reaction, it was found that the sum of squared singular values of the solutions of the CPSCF equation gives the maximum peak at the transition state structure and the shoulder of the potential energy curve, which clearly explains the process of electron transfer and bond formation in this reaction. The NRO-based reaction analysis method has been demonstrated to be universal and robust for describing sophisticated reaction mechanisms., Cambridge University Press (CUP), English, Technical report
• 温和な条件下でのアンモニア合成を目指したCo/MgO触媒へのBaO添加効果
  佐藤勝俊; 佐藤勝俊; 宮原伸一郎; 毛利広野; 岩佐豪; 岩佐豪; 武次徹也; 武次徹也; 永岡勝俊; 永岡勝俊, 触媒討論会討論会A予稿集(CD-ROM), 128th, 2021
• Construction of a Hamiltonian system with reduced degrees of freedom extracted by principal component analysis
  田中綾一; 水野雄太; 水野雄太; 堤拓朗; TSITSVERO Mikhail; 武次徹也; 武次徹也; 小松崎民樹; 小松崎民樹, 分子科学討論会講演プログラム&要旨(Web), 15th, 2021
• Observation-time scale hierarchies of reaction network and its correlated structural similarity
  永幡裕; 武次徹也; 武次徹也; 前田理; 前田理; 小松崎民樹; 小松崎民樹, 分子科学討論会講演プログラム&要旨(Web), 15th, 2021
• 光免疫治療に資するX線誘導による生体深部腫瘍での選択的分子解離の探索(Explore of X-ray induced selective molecular degradation for photoimmuno-therapy targeting deep tissues)
  横谷 明徳; 藤井 健太郎; 渡辺 立子; 平戸 未彩紀; 中川 桂一; 稲波 修; 武次 徹也; 小川 美香子, 日本放射線影響学会大会講演要旨集, 63回, 122, 122, Oct. 2020
  (一社)日本放射線影響学会, English
• 多次元データ縮約法に基づいた固有反応座標及び反応経路ネットワークの可視化
  堤拓朗; 小野ゆり子; 荒井迅; 武次徹也; 武次徹也, 日本化学会春季年会講演予稿集(CD-ROM), 99th, 2019
• 時間分解光電子分光法によるo-ニトロフェノールの超高速光解離反応の観測
  新田優輝; SCHALK Oliver; 和田諒; 堤拓朗; 武次徹也; 武次徹也; 金島圭佑; 関川太郎, 分子科学討論会講演プログラム&要旨(Web), 13th, 2019
• 機械学習を利用した第一原理MDトラジェクトリの自動分類
  小林正人; 原渕祐; 堤拓朗; 小野ゆり子; 瀧川一学; 武次徹也, 日本コンピュータ化学会年会講演予稿集, 2018, 73, 03 Nov. 2018
  Japanese
• 桂皮酸エステルのtrans→cis光異性化の体系的な研究
  木下真之介; 宮崎康典; 井口佳哉; 江幡孝之; 井上昂輔; 長森啓悟; 鬼塚侑樹; 高口博志; 赤井伸行; 白男川貴史; 白男川貴史; 江原正博; 江原正博; 山崎馨; 原渕祐; 原渕祐; 前田理; 武次徹也, 分子科学討論会講演プログラム&要旨(Web), 12th, 2018
• DSAP類縁体のC‐C単結合長に関する理論的研究:環境効果の検討
  黒田悠介; 小林正人; 武次徹也, 基礎有機化学討論会要旨集, 28th, 253, 07 Sep. 2017
  Japanese
• Nonradiative decay process and trans→cis isomerization of p‐, m‐, o‐hydroxy methylcinnamate
  KINOSHITA Sin‐nosuke; MIYAZAKI Yasunori; INOKUCHI Yoshiya; EBATA Takayuki; SUMIDA Masataka; ONITSUKA Yuuki; KOHGUCHI Hiroshi; AKAI Nobuyuki; EHARA Masahiro; YAMAZAKI Kaoru; MAEDA Satoshi; HARABUCHI Yu; TAKETSUGU Tetsuya, 化学反応討論会講演要旨集, 33rd, 71, 07 Jun. 2017
  English
• チオール分子で保護された金クラスターの励起状態と発光機構の解明
  蝦名昌徳; 原渕祐; 岩佐豪; 武次徹也, ナノ学会大会講演予稿集, 15th, 153, 10 May 2017
  Japanese
• クラスターモデルでの酸化物担持金属クラスター触媒の電子物性
  岩佐豪; 武次徹也, ナノ学会大会講演予稿集, 15th, 160, 10 May 2017
  Japanese
• 量子化学計算とインフォマティクスを用いたメタン水蒸気改質触媒能の評価
  小林正人; 小野田遼; 武次徹也, 触媒討論会講演予稿集, 119th, 234, 10 Mar. 2017
  Japanese
• 速度定数行列縮約法を用いた反応経路自動探索の効率化:多成分連結反応への応用
  住谷陽輔; 武次徹也; 前田理, 日本化学会春季年会講演予稿集(CD-ROM), 97th, ROMBUNNO.1A7‐47, 03 Mar. 2017
  Japanese
• 分割統治法とHartree‐Fock‐Bogoliubov法を組み合わせた大規模強相関系電子状態計算手法の開発とグラフェンナノリボンへの適用
  児玉良輔; 小林正人; 武次徹也, 日本化学会春季年会講演予稿集(CD-ROM), 97th, ROMBUNNO.1A7‐12, 03 Mar. 2017
  Japanese
• Pt(111)表面によるCO酸化に対する反応経路ネットワークとその解析
  杉山佳奈美; 高木牧人; 斉田謙一郎; 前田理; 武次徹也, 日本化学会春季年会講演予稿集(CD-ROM), 97th, ROMBUNNO.4A8‐06, 03 Mar. 2017
  Japanese
• 分割統治(DC)法に基づいた大規模量子化学計算における誤差の自動制御化
  藤森俊和; 小林正人; 武次徹也, 日本化学会春季年会講演予稿集(CD-ROM), 97th, ROMBUNNO.1A7‐11, 03 Mar. 2017
  Japanese
• 塩化アルミニウムを用いるFriedel‐Craftsアルキル化反応の触媒機構及び速度論に関する理論的研究
  三瓶匡史; 住谷陽輔; 前田理; 武次徹也, 日本化学会春季年会講演予稿集(CD-ROM), 97th, ROMBUNNO.1F5‐47, 03 Mar. 2017
  Japanese
• 表面モデル計算と統計手法によるメタン水蒸気改質触媒活性の評価
  小野田遼; 小林正人; 武次徹也, 日本化学会春季年会講演予稿集(CD-ROM), 97th, ROMBUNNO.2PA‐202, 03 Mar. 2017
  Japanese
• para-,meta-,ortho-hydroxy methylcinnamateの無輻射緩和経路とtrans→cis異性化の研究
  木下真之介; 宮崎康典; 井口佳哉; 江幡孝之; 住田聖太; 鬼塚侑樹; 高口博志; 赤井伸行; 白男川貴史; 白男川貴史; 江原正博; 江原正博; 山崎馨; 原渕祐; 原渕祐; 前田理; 武次徹也, 分子科学討論会講演プログラム&要旨(Web), 11th, 2017
• Hydroxy methylcinnamateにおける無輻射失活経路の置換位置依存性
  山崎馨; 山崎馨; 山崎馨; 木下真之介; 宮崎康典; 住田聖太; 鬼塚侑樹; 高口博志; 井口佳哉; 赤井伸行; 白男川貴史; 白男川貴史; 江原正博; 江原正博; 原渕祐; 原渕祐; 前田理; 原渕祐; 武次徹也; 武次徹也; 江幡孝之, 分子科学討論会講演プログラム&要旨(Web), 11th, 2017
• 分子の分かれ道 － 反応経路が分岐したとき分子はどちらの道を選ぶのか？
  武次徹也; 原渕祐; 小野ゆり子; 前田理, 化学, 71, 7, 70, 71, 2016, [Invited]
  Japanese, Introduction commerce magazine
• 紫外-遠紫外pump-probe法によるメチルシンナメート誘導体の無輻射緩和ルートの解明
  木下真之介; 江幡孝之; 宮崎康典; 井口佳哉; 住田聖太; 鬼塚侑樹; 高口博志; 山崎馨; 山崎馨; 原渕祐; 原渕祐; 武次徹也; 武次徹也; 前田理; 前田理; 江原正博, 分子科学討論会講演プログラム&要旨(Web), 10th, 2016
• 時間解像度に依存した反応ネットワークの階層的変化とその予測手法の開発
  永幡裕; 前田理; 寺本央; 武次徹也; 小松崎民樹, 分子科学討論会講演プログラム&要旨(Web), 10th, ROMBUNNO.3P151 (WEB ONLY), 2016
  Japanese
• Bond Selective Probe by Time-Resolved Photoelectron Spectroscopy: Ring-Opening Dynamics of 1,3-Cyclohexadiene
  Ryo Iikubo; Taro Sekikawa; Yu Harabuchi; Tetsuya Taketsugu, 2016 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO), 2016
  English
• Bond Selective Probe by Time-Resolved Photoelectron Spectroscopy: Ring-Opening Dynamics of 1,3-Cyclohexadiene
  Ryo Iikubo; Taro Sekikawa; Yu Harabuchi; Tetsuya Taketsugu, 2016 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO), 2016
  English
• Estimation of isomer energies by sparse modeling with local explanatory variables
  Onoda Haruka; Kobayashi Masato; Taketsugu Tetsuya, Proceedings of the Symposium on Chemoinformatics, 2016, 0, P15, 2016
  If the molecular energy obtained from the quantum chemical calculation can be modeled with local explanatory variables such as atomic charges, it is possible to drastically reduce the computational cost. We attempted to model the total energies of C₃H₆O₂ isomers by using Mulliken, Lowdin, natural, and ESP charges as the explanatory variables. By applying the MC+ regression, we could obtain a model showing good agreement with the calculated energy with a couple of explanatory variables. Applying this modeling scheme to the isomers of C₈H₁₀O₂, C₉H₁₀O₂, C₉H₁₀O₃, and C₁₀H₁₂O₂, however, resulted in failing to obtain good models. By adding the numbers of 3 to 8 membered rings as the explanatory variable, we could obtain good sparse models. In addition, it was found that all these sparse models contain the largest natural charge and the number of 6-membered rings as the explanatory variable., Division of Chemical Information and Computer Sciences The Chemical Society of Japan, Japanese
• Development of efficient time evolution method based on operator transformation
  Akama Tomoko; Kobayashi Osamu; Nanbu Shinkoh; Taketsugu Tetsuya, Proceedings of the Symposium on Chemoinformatics, 2016, 0, P10, 2016
  Real-time propagation (RT) of time-dependent theories, such as time-dependent Hartree-Fock (TDHF) method and time-dependent density functional theory (TDDFT), have been applied to theoretically describing electron dynamics. However, RT calculations are computationally demanding, because of evaluation of time-evolution operator by conventional numerical integration such as the Runge-Kutta method. In this study, we developed the three-term recurrence-relation (3TRR) method as an efficient time-evolution method for electron dynamics, being inspired by the real-wave-packet method for nuclear wave packet dynamics with time-dependent Schr&ouml;dinger equation. The basic formula of this approach was derived by introducing a transformation of the operator using the arcsine function. Since this operator transformation causes transformation of time, we derived the relation between original and transformed time. We applied this 3TRR method to equation of motion for density matrix in RT-THDF/TDDFT. 3TRR method achieved about four times faster RT-TDHF calculation than conventional fourth-order Runge-Kutta method., Division of Chemical Information and Computer Sciences The Chemical Society of Japan, Japanese
• Specifying primary factors in the catalytic activity of metal clusters based on quantum chemical calculations and machine learning
  Kobayashi Masato; Iwasa Takeshi; Gao Min; Takagi Makito; Maeda Satoshi; Taketsugu Tetsuya, Proceedings of the Symposium on Chemoinformatics, 2016, 0, O18, 2016
  Because catalytic activities of metal nano clusters depend on the composition, size, environment, and structural isomers of the cluster, it has been difficult to elucidate the primary factors in their catalytic activities. In this study, we attempted to extract the factors in the catalytic activity using the sparse modeling techniques and the systematic quantum chemical calculations assisted by the automatic search of reaction pathways. In particular, the transition state energies for NO dissociation on Cu13 clusters were modeled with the orbital energies and local indices by the LASSO, SCAD, and MC+ regressions. It was found that the transition state energy negatively correlates with the LUMO energy. The SCAD and MC+ regressions could generate more compact and better models with higher correlation factors than the LASSO regression., Division of Chemical Information and Computer Sciences The Chemical Society of Japan, Japanese
• 単一次数高調波光源による気相分子の時間分解光電子分光
  関川太郎; 飯窪亮; 原渕祐; 佐藤壮太; 武次徹也; 萱沼洋輔, レーザー研究, レーザー学会誌, 43, 12, 833, 837, 2015, [Invited]
  レーザー学会, Japanese, Report scientific journal
• 複雑分子系の異性化反応ネットワークに埋め込まれた時間階層構造の解読
  永幡裕; 前田理; 寺本央; 寺本央; LI Chun‐Biu; 堀山貴史; 武次徹也; 小松崎民樹; 小松崎民樹, 分子科学討論会講演プログラム&要旨(Web), 9th, ROMBUNNO.1P088 (WEB ONLY), 2015
  Japanese
• Ultrafast and Photodissociation Dynamics of 1,2-Butadiene Studied by Photoelectron Spectroscopy
  Ryo Iikubo; Takehisa Fujiwara; Taro Sekikawa; Yu Harabuchi; Tetsuya Taketsugu, ULTRAFAST PHENOMENA XIX, 162, 44, 47, 2015
  English
• Ultrafast Relaxation and Photodissociation Dynamics of 1,3-Butadiene Studied by Probing Molecular Orbitals
  A. Makida; T. Fujiwara; Yu Harabuchi; T. Taketsugu; T. Sekikawa, ULTRAFAST PHENOMENA XIX, 162, 40, 43, 2015
  English
• Ultrafast and Photodissociation Dynamics of 1,2-Butadiene Studied by Photoelectron Spectroscopy
  Ryo Iikubo; Takehisa Fujiwara; Taro Sekikawa; Yu Harabuchi; Tetsuya Taketsugu, ULTRAFAST PHENOMENA XIX, 162, 44, 47, 2015
  English
• 22pBG-13 Theoretical method for the interaction between non-uniform near-field and molecular vibrations
  Iwasa T; Taketsugu T, Meeting Abstracts of the Physical Society of Japan, 70, 0, 696, 696, 2015
  The Physical Society of Japan (JPS), Japanese
• Photodissociation of 1,2-butadiene studied by time-resolved molecular orbital spectroscopy using single-order high harmonic pulses
  R. Iikubo; T. Fujiwara; T. Sekikawa; Y. Harabuchi; T. Taketsugu; Y. Kayanuma, Optics InfoBase Conference Papers, 21 Jul. 2014
• 1,3‐butadineにおける励起状態の超高速緩和の観測
  関川太郎; 槇田歩; 原渕祐; 武次徹也, 応用物理学会春季学術講演会講演予稿集(CD-ROM), 61st, ROMBUNNO.17P-F7-4, 03 Mar. 2014
  Japanese
• 複雑分子系の異性化反応ネットワークに埋め込まれた時間階層構造の抽出
  永幡裕; 前田理; 寺本央; LI Chun‐Biu; 堀山貴史; 武次徹也; 小松崎民樹, 分子科学討論会講演プログラム&要旨(Web), 8th, ROMBUNNO.1E15 (WEB ONLY), 2014
  Japanese
• Ultrafast Relaxation and Photodissociation Dynamics of 1,3-Butadiene Studied by Probing Molecular Orbitals
  A. Makida; T. Fujiwara; Yu Harabuchi; T. Taketsugu; T. Sekikawa, 2014 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO), 2014-January, 2014
  English
• Ultrafast Relaxation and Photodissociation Dynamics of 1,3-Butadiene Studied by Probing Molecular Orbitals
  A. Makida; T. Fujiwara; Yu Harabuchi; T. Taketsugu; T. Sekikawa, 2014 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO), 2014
  English
• Theoretical studies on the mechanism of photochemical reactions by using automated reaction path search methods
  MAEDA Satoshi; TAKETSUGU Tetsuya; XIAO Hongyan; MOROKUMA Keiji, 化学反応討論会講演要旨集, 29th, 32, 33, 05 Jun. 2013
  English
• Exploring pathways for the reaction between CH3CHO-HCOOH clusters ad OH radicals: Prediction of reactivity and branching ratio
  SUMIYA Yosuke; MAEDA Satoshi; TAKETSUGU Tetsuya, 化学反応討論会講演要旨集, 29th, 105, 05 Jun. 2013
  English
• New Channel of the Water Gas Shift Reaction
  OHNO Koichi; HARABUCHI Yu; MAEDA Satoshi; TAKETSUGU Tetsuya, 化学反応討論会講演要旨集, 29th, 104, 05 Jun. 2013
  English
• Systematic exploration of reaction pathways between CH3NH2 and OH
  FURUHAMA Ayako; IMAMURA Takashi; MAEDA Satoshi; TAKETSUGU Tetsuya, 化学反応討論会講演要旨集, 29th, 91, 05 Jun. 2013
  English
• GRRM/AFIR法による光環化付加反応機構の検討
  前田理; 原渕祐; 武次徹也; 諸熊奎治, 日本化学会講演予稿集, 93rd, 2, 440, 08 Mar. 2013
  Japanese
• GRRM法とSF‐TDDFT法を組み合わせた最小エネルギー円錐交差構造自動探索:大きな分子への適用へ向けて
  原渕祐; 前田理; 武次徹也; 嶺澤範行; 諸熊奎治, 日本化学会講演予稿集, 93rd, 2, 440, 08 Mar. 2013
  Japanese
• The h-BN surface effect on CO oxidation reaction catalyzed by supported gold atom
  Min Gao; Andrey Lyalin; Tetsuya Taketsugu, Journal of Physics: Conference Series, 438, 1, 2013
  Institute of Physics Publishing, English
• 反応経路自動探索法による2‐シロキシフランを用いるvinylogous Mannich‐type反応の機構解明
  植松遼平; 前田理; 武次徹也, 基礎有機化学討論会要旨集, 23rd, 206, 05 Sep. 2012
  Japanese
• 反応経路自動探索法の開発と合成反応機構の量子化学的系統解明
  前田理; 植松遼平; 武次徹也; 諸熊奎治, 基礎有機化学討論会要旨集, 23rd, 56, 57, 05 Sep. 2012
  Japanese
• o‐フェニレンジアミン3d金属錯体が示す光水素発生反応
  張浩徹; 松本剛; 上野導; 中山哲; 武次徹也; 小林厚志; 加藤昌子, 配位化合物の光化学討論会講演要旨集, 24th, 41, 42, 06 Aug. 2012
  Japanese
• トランスアゾベンゼンの励起振動分光と異性化機構に関する理論的研究
  原渕祐; 石井萌; 佐藤公則; 野呂武司; 武次徹也, 日本化学会講演予稿集, 92nd, 2, 277, 09 Mar. 2012
  Japanese
• Support effects on the catalytic activity of gold clusters
  Min Gao; Andrey Lyalin; Tetsuya Taketsugu, ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 243, Mar. 2012, [Peer-reviewed]
  English, Summary international conference
• Theoretical study on photo-induced isomerization and proton transfer in 7-azaindole-((H2O)(3) cluster
  Xuefang Yu; Shohei Yamazaki; Tetsuya Taketsugu, ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 243, Mar. 2012
  English, Summary international conference
• 全対称振動座標が関与する分岐反応経路の理論的解析
  原渕祐; 武次徹也, 日本化学会講演予稿集, 91st, 2, 385, 11 Mar. 2011
  Japanese
• Mechanism of the excited-state double proton transfer in 7-azaindole dimer: DFT and ab initio study
  Xuefang Yu; Shohei Yamazaki; Tetsuya Taketsugu, ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 241, Mar. 2011
  English, Summary international conference
• 貴金属フリー・ナノハイブリッド触媒の創製 (特集 代替材料の最先端)
  魚崎 浩平; 加藤 昌子; 武次 徹也; 村越敬, 化学経済, 57, 7, 55, 60, Jun. 2010
  化学工業日報社, Japanese
• Catalitic Activity of Gold Clusters
  Andrey Lyalin; Tetsuya Taketsugu, ISACC 2009: FOURTH INTERNATIONAL SYMPOSIUM ON ATOMIC CLUSTER COLLISIONS, 1197, 65, 75, 2009, [Invited]
  English, Introduction international proceedings
• Metal-phthalocyanione complexes
  稲辺 保; 武次 徹也; 松田 真生, Solid state physics, 43, 11, 795, 808, Nov. 2008
  アグネ技術センタ-, Japanese
• 21aTC-9 Photoemission spectroscopy in molecular conductor TPP[Fe(Pc)(CN)_2]_2
  Hanasaki N; Tanabe M; Wakita T; Muraoka Y; Yokoya T; Nogami Y; Matsuda M; Tajima H; Taketsugu T; Yu Derrick Ethelbhert C; Naito T; Inabe T, Meeting abstracts of the Physical Society of Japan, 63, 2, 745, 745, 25 Aug. 2008
  The Physical Society of Japan (JPS), Japanese
• 計算科学の横断的連携へ
  TAKETSUGU Tetsuya, iiC-HPC, 9, 4, 9, 2006, [Invited]
  Japanese, Others
• 理系研究者にとっての外国語(外国語と私)
  武次 徹也, 生活工学研究, 6, 2, 163, 164, 2004
  お茶の水女子大学, Japanese
• 3B07 The influence of the fluorophilic interaction on the appearance of liquid crystalline phases
  Yano Megumi; Taketsugu Tetsuya; Hori Kayako; Okamoto Hiroaki; Takenaka Shunsuke, Proceedings of Japanese Liquid Crystal Society Annual meeting, 2002, 2002, 239, 240, 09 Oct. 2002
  Crystal structures were determined for alkyl 4- [2- (perfluorooctyl) ethoxy] benzoates (F8-n), in order to clarify the intermolecular interaction responsible for the liquid crystalline behavior depending on the alkyl chain lengths. It became clear that the aggregation of perfluoroalkyl chains is formed in the crystal structure of a member which shows S_A phase but not in those with no mesophases. In this work, we have determined the crystal structure of F8-4. It turns out that crystal structures change systematically according to the alkyl chain lengths. Energy calculation for each structur..., 日本液晶学会, Japanese
• A new stage of theoretical chemistry: applications to reactions involving zeolite and transition metals
  N.Tajima; Y.Nakao; F.Tohyama; T.Taketsugu; K.Hirao, The Bulletin of the Cluster Science and Technology, 3, 2, 2000, [Invited]
  Introduction scientific journal
• A least-action variational method for determining tunneling paths in multidimensional system.
  T Taketsugu; K Hirao, ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 215, U177, U177, Apr. 1998
  English, Summary international conference
• Approaches to bifurcating reaction path.
  TAKETSUGU TETSUYA; TAJIMA NOBUO; YANAI TAKESHI; HIRAO KIMIHIKO, 分子構造総合討論会講演要旨集, 1996, 9, Oct. 1996
  Japanese
• Theoretical Study of Electronic and Geometric Structures of a Series of Lanthanoid Compounds LnCl3 (Ln=La-Lu).
  TSUCHIYA TAKASHI; NAKANO HARUYUKI; TAKETSUGU TETSUYA; HIRAO KIMIHIKO, 分子構造総合討論会講演要旨集, 1996, 267, Oct. 1996
  Japanese
• Theoretical Study of Electronic and Geometric Structures of a Series of Lanthanoid Compounds LnCl3 (Ln=La-Lu).
  TSUCHIYA TAKASHI; NAKANO HARUYUKI; TAKETSUGU TETSUYA; HIRAO KIMIHIKO, 希土類, 28, 238, 239, May 1996
  Japanese
• 分子内の振動混合―DRC法の応用
  武次徹也; 平野恒夫, 分子構造総合討論会講演要旨集, 1994, 12, Sep. 1994
  Japanese
• 水溶液中の蟻酸イオンに関する量子化学計算
  神林弥生; 武次徹也; 中野隆志; 平野恒夫, 分子構造総合討論会講演要旨集, 1993, 315, Oct. 1993
  Japanese
• 分岐発生のメカニズム
  武次徹也; 平野恒夫, 分子構造総合討論会講演要旨集, 1993, 202, Oct. 1993
  Japanese
• 電場による振動励起
  武次徹也; 平野恒夫, 分子構造総合討論会講演要旨集, 1992, 100, Sep. 1992
  Japanese
• 振動混合による反応性理論
  武次徹也; 平野恒夫, 分子構造総合討論会講演要旨集, 1990, 101, Oct. 1990
  Japanese

• 密度汎関数法による量子化学計算 (KS化学専門書)
  常田貴夫; 武次徹也; 小林正人; 岩佐豪; Andrey Lyalin; 斉田謙一郎; 小野ゆり子; 堤拓朗; 和田諒; 赤間知子
  講談社, 29 May 2025, 4065396786, 256, Japanese, Textbook, [Joint editor]
• ケモインフォマティクスにおけるデータ収集の最適化と解析手法
  岩佐豪; 小林正人; 武次徹也, 第3章 第2節 計算化学研究におけるスパースモデリングの応用 pp 92-100
  技術情報協会, Apr. 2023, 657, pp 92-100, Japanese, Scholarly book, [Contributor]
• 計算化学
  Jensen, Frank; 五十幡, 康弘; 内田, 希; 神谷, 宗明; 北, 幸海; 小林, 正人 (物理化学); 佐藤, 啓文; 重田, 育照; 砂賀, 彩光; 武次, 徹也; 常田, 貴夫; 長谷川, 淳也; 波田, 雅彦; 森, 聖治; 後藤, 仁志; 立川, 仁典; 長嶋, 雲兵
  森北出版, Mar. 2023, 9784627242333, xx, 882p, Japanese
• Time-Dependent Density Functional Theory: Nonadiabatic Molecular Dynamics
  Tetsuya Taketsugu; Takuro Tsutsumi; Yu Harabuchi; Takao Tsuneda, Chapter 2. On-the-fly excited-state molecular dynamics study based on spin-flip TDDFT approach: photo-branching reaction of stilbene and stilbene derivatives, pp39-73
  Jenny Stanford Publishing, 29 Dec. 2022, 9814968420, 504, pp39-73, English, Scholarly book, [Peer-reviewed], [Contributor]
• Spectroscopy and computation of hydrogen-bonded systems
  Tetsuya Taketsugu; Yusuke Ootani, chapter 3. Trajectory on-the-fly Molecular Dynamics Approach to Tunneling Splitting in the Electronic Ground and Excited States, pp65-80
  Wiley-VCH, 27 Dec. 2022, 3527349723, 544, pp65-80, English, Scholarly book, [Peer-reviewed], [Contributor]
• 化学便覧 基礎編 改訂6版
  武次徹也; 小林正人, 「理論化学，計算化学，情報化学」17章2.3節 化学反応
  丸善出版, Jan. 2021, 9784621305218, xviii, 1509p, pp1276-1278, Japanese, Dictionary or encycropedia, [Peer-reviewed], [Contributor]
• 触媒の劣化対策、長寿命化
  武次徹也; Andrey Lyalin, 第１２章 触媒の貴金属低減化、貴金属フリー技術 第6節 新電極触媒BN/Au：理論提案から実験実証へ
  技術情報協会, Nov. 2020, 9784861048142, 579p, pp 571-579, Japanese, Scholarly book, [Contributor]
• 化学 : 物質の構造と性質を理解する
  新しい化学教育研究会, 第３章 化学結合と分子構造
  学術図書出版社, Apr. 2019, 9784780607635, iv, 333p, Japanese, [Joint work]
• Frontiers of Quantum Chemistry
  Tetsuya Taketsugu; Yu Harabuchi, Ab initio molecular dynamics study on photoisomerization reactions: Applications to azobenzene and stilbene
  Springer, 2017, pp431-453, [Contributor]
• 新版 すぐできる 量子化学計算ビギナーズマニュアル (KS化学専門書)
  武次徹也; 平尾公彦
  講談社サイエンティフィク, Mar. 2015, 4061543881, 224, Japanese, Scholarly book, [Editor]
• π-Stacked Polymers and Molecules: Theory, Synthesis, and Properties
  Takao Tsuneda; Tetsuya Taketsugu, π-Stacking on Density Functional Theory: A review
  Springer, 2013, pp 245-270, [Contributor]
• Advances in Quantum Monte Carlo
  Akira Nakayama; Tetsuya Taketsugu, Chapter 3. Enhancement of sampling efficiency in ab initio Monte Carlo simulations using an auxiliary potential energy surface
  ACS symposium series vol 1094, 2012, pp 27-40, [Contributor]
• Hydrogen Bonding and Transfer in the Excited State
  Tetsuya Taketsugu; Daisuke Kina; Akira Nakayama; Takeshi Noro; Mark S. Gordon, QM/MM Study of Excited State Solvation Dynamics of Biomolecules
  Wiley, 2010, pp. 579-588, [Contributor]
• すぐできる 量子化学計算ビギナーズマニュアル (KS化学専門書)
  武次 徹也; 平尾 公彦; 武次 徹也; 平尾 公彦
  講談社サイエンティフィク, Apr. 2006, 406154330X, 236, Japanese, [Editor]

  
• 早わかり分子軌道法 (化学サポートシリーズ)
  武次 徹也; 平尾 公彦
  裳華房, Jan. 2003, 4785334096, 114, Japanese, [Joint work]

  
• The Transition State: A Theoretical Approach
  Tetsuya Taketsugu; Kimihiko Hirao, 3. Molecular Symmetry and Transition State
  Kodansha-Gordon and Breach Science Publishers, 1999, pp45-63, [Contributor]
• Theory of Chemical Reaction in terms of Normal Modes of Vibration
  Tetsuya Taketsugu
  Thesis (The Univ. of Tokyo), Mar. 1994, [Single work]
• 分子軌道法MOPACガイドブック”第２版
  武次 徹也, １０章．遷移状態の計算法とキーワード SADDLE,NLLSQ,TS 等の使用法
  海文堂, 1994, pp187-203, [Contributor]

• Theoretical suggestion and experimental proof for functionalization of h-BN by gold as electrocatalysts for ORR and HER
  Tetsuya Taketsugu; Andrey Lyalin; Min Gao; Kohei Uosaki
  256th ACS National Meeting "Fundamental Understanding of Catalysis at Interface through Computational Approach", 19 Aug. 2018, English, Invited oral presentation
  Boston, [Invited], [International presentation]
• Reaction Path Concept in Quantum Chemistry and Dynamics Effects
  TAKETSUGU Tetsuya
  Geometry of Chemical Reaction Dynamics in Gas and Condensed Phases, TSRC workshop, 17 Jul. 2018, English, Invited oral presentation
  Telluride, [Invited], [International presentation]
• Dynamic Reaction Routes beyond the IRC network
  TAKETSUGU Tetsuya
  7th JCS SYMPOSIUM (Quantum chemistry, from methodology to applications in organic, inorganic, biochemistry and material sciences), 21 May 2018, English, Invited oral presentation
  PRAGUE, [Invited], [International presentation]
• 理論と実験のインタープレイから生まれた新しい触媒：BN/Au
  武次徹也; Andrey Lyalin; Min Gao; 魚崎浩平
  ワークショップ「理論と実験の融合による高難度物質変換の反応機構解明にむけて」, 11 May 2018, Japanese, Invited oral presentation
  札幌, [Invited], [Domestic Conference]
• 固有反応座標と動力学効果
  武次徹也
  ワークショップ 「複合系の理論化学・計算化学：最近の研究状況と展望」, 21 Apr. 2018, Japanese, Invited oral presentation
  京都, [Invited], [Domestic Conference]
• Theoretical study of reactivity of gold clusters: Structural effects and support effects
  Tetsuya Taketsugu
  APS March Meeting "Nano and sub-nano clusters as the smallest and highly-tunable interfaces", 05 Mar. 2018, English, Invited oral presentation
  Los Angels, [Invited], [International presentation]
• 理論計算による未知触媒開発と未知反応機構解明
  武次徹也
  計算材料学センター セミナーシリーズ スパコンプロフェッショナル No.11, 23 Feb. 2018, Japanese, Invited oral presentation
  仙台, [Invited], [Domestic Conference]
• 量子化学研究の最新の展開：振動状態理論・反応経路網・ダイナミクス
  武次徹也
  2017 年度「物質階層原理研究」研究報告会, 13 Feb. 2018, Japanese, Invited oral presentation
  和光, [Invited], [Domestic Conference]
• Theoretically inspired new catalyst: boron nitride with gold
  TAKETSUGU Tetsuya
  2018 Mesilla Chemistry Workshop on Interplay between Theory and Experiment in Nanocatalysis, 04 Feb. 2018, English, Invited oral presentation
  Mesilla, [Invited], [International presentation]
• 元素戦略にもとづく触媒開発研究 ～理論計算と実験実証のインタープレイ～
  武次徹也
  スーパーコンピュータワークショップ2017「機能性材料設計への最新の計算科学アプローチ」, 23 Jan. 2018, Japanese, Invited oral presentation
  東岡崎, [Invited], [Domestic Conference]
• 隠れた反応経路 - 固有反応座標を超えて
  武次徹也
  化学科主催研究会「お茶の水女子大学の理論化学と計算化学」, 23 Dec. 2017, Japanese, Invited oral presentation
  茗荷谷, [Invited], [Domestic Conference]
• 解離性再結合反応の 第一原理分子動力学シミュレーション
  武次徹也
  宇宙生命計算科学連携拠点第 3 回ワークショップ, 20 Nov. 2017, Japanese, Invited oral presentation
  筑波, [Invited], [Domestic Conference]
• 北大理論化学グループの元素戦略プロジェクト：これまでの成果と今後の計画
  武次徹也; 岩佐豪; 高敏; 小林正人; 前田理; 中山哲; Andrey Lyalin; Raman Singh
  ESICB電子論 second kick-off会議, 13 Nov. 2017, Japanese, Invited oral presentation
  京都, [Invited], [Domestic Conference]
• Theoretical Suggestion and Experimental Proof for Novel Catalyst: Boron Nitride with Gold
  TAKETSUGU Tetsuya
  The 2017 International Conference on Functional Carbons (ICFC), 01 Nov. 2017, English, Invited oral presentation
  Taipei, [Invited], [International presentation]
• Reaction-path bifurcation analyses based on Valley-Ridge transition and global reaction route mapping
  Tetsuya Taketsugu; Yu Harabuchi; Yuriko Ono; Takuro Tsutsumi; Satoshi Maeda
  The 11th Triennial Congress of the World Association of Theoretical and Computational Chemists (WATOC 2017), 27 Aug. 2017, English, Oral presentation
  Munich, [International presentation]
• Computational approach to design of non-platinum catalyst for oxygen reduction reaction: boron nitride with gold
  Tetsuya Taketsugu; Andrey Lyalin; Min Gao; Kohei Uosaki
  The 21st International Annual Symposium on Computational Science and Engineering (ANSCSE21), 03 Aug. 2017, English, Invited oral presentation
  Pathum Thani, Thailand, [Invited], [International presentation]
• A Hidden Feature in Static Intrinsic Reaction Coordinate Analysis: Bifurcation
  TAKETSUGU Tetsuya
  3rd Japan-Thai workshop on Theoretical and Computational Chemistry 2017, 14 Jul. 2017, English, Invited oral presentation
  Yokohama, [Invited], [International presentation]
• Theoretical approach to reaction-path bifurcation
  TAKETSUGU Tetsuya
  INTERNATIONAL SYMPOSIUM ON PURE & APPLIED CHEMISTRY (ISPAC) 2017, 08 Jun. 2017, English, Invited oral presentation
  Ho Chi Minh, Vietnam, [Invited], [International presentation]
• AIMD study on pipi*-excited substituted-stilbene
  Tetsuya Taketsugu; Rina Yamamoto; Takuro Tsutsumi; Yu Harabuchi; Satoshi Maeda
  57th Sanibel Symposium, 19 Feb. 2017, English, Poster presentation
  St. Simons Island, [International presentation]
• Ab initio MD study of branching reactions in the excited-state potential energy surface
  TAKETSUGU Tetsuya
  GAMESS7557 Meeting, 15 Jan. 2017, English, Invited oral presentation
  Kauai, [Invited], [International presentation]
• 反応経路自動探索法の金属クラスター触媒への応用と表面触媒反応への展開
  武次徹也; 前田 理; 岩佐 豪; 小林正人; 高 敏; 中山 哲; Andrey Lyalin
  ESICB触媒検討会, 12 Jan. 2017, Japanese, Invited oral presentation
  京都, [Invited], [Domestic Conference]
• 理論計算が拓く非白金燃料電池触媒探索の試み
  武次徹也
  ポスト「京」重点課題５ 「エネルギーの高効率な創出，変換・貯蔵，利用の新規基盤技術の開発」第３回公開シンポジウム, 15 Dec. 2016, Japanese, Invited oral presentation
  東京, [Invited], [Domestic Conference]
• 触媒開発に理論化学は役に立つか？ 未知触媒と未知反応機構へのアプローチ
  武次徹也
  住友化学講演会, 08 Dec. 2016, Japanese, Public discourse
  千葉, [Invited], [Domestic Conference]
• Ab Initio Approach to Photoreaction Dynamics
  TAKETSUGU Tetsuya
  Thai-Japan Symposium in Chemistry, 15 Nov. 2016, English, Invited oral presentation
  Chiang Mai, [Invited], [International presentation]
• On-the-fly dynamics study on the photoisomerization mechanism of stilbene and its derivative
  TAKETSUGU Tetsuya
  Japan-France-Spain Joint-Symposium on Theoretical and Computational Science of Complex Systems, 26 Oct. 2016, English, Invited oral presentation
  Kyoto, [Invited], [International presentation]
• Theoretical study of substituent effects on excited-state dynamics of stilbene
  TAKETSUGU Tetsuya
  2nd Japan-Thai workshop on Theoretical and Computational Chemistry 2016, 21 Sep. 2016, English, Invited oral presentation
  Yokohama, [Invited], [International presentation]
• 反応経路分岐の理論化学
  武次徹也
  有機反応機構研究会, 05 Sep. 2016, Japanese, Invited oral presentation
  長崎, [Invited], [Domestic Conference]
• Ab initio study of photo-isomerization reaction dynamics
  TAKETSUGU Tetsuya
  INTERNATIONAL SYMPOSIUM ON PURE & APPLIED CHEMISTRY (ISPAC) 2016, 16 Aug. 2016, English, Invited oral presentation
  Kuching, Malaysia, [Invited], [International presentation]

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• 化学特別講義Ⅱ, 2024年, 学士課程, 総合教育部
• 分子化学Ａ（分子理論化学）, 2024年, 修士課程, 総合化学院
• 物理化学Ⅰ, 2024年, 学士課程, 理学部
• 計算機実習, 2024年, 学士課程, 理学部
• 化学特別講義Ⅱ, 2024年, 学士課程, 理学部

• 理論化学会
• American Chemical Society
• 分子科学会
• 日本化学会

• Theoretical Chemistry Analysis of Superatomic Materials
  Grants-in-Aid for Scientific Research
  01 Apr. 2026 - 31 Mar. 2031
  武次 徹也; 岩佐 豪
  Japan Society for the Promotion of Science, Grant-in-Aid for Transformative Research Areas (A), Hokkaido University, 26H00397
• Theoretical study of reaction path bifurcation mapped on the global reaction route map
  Grants-in-Aid for Scientific Research
  19 Jul. 2016 - 31 Mar. 2019
  Taketsugu Tetsuya; MAEDA Satoshi
  The intrinsic reaction coordinate (IRC) is defined as a static reaction path for an elementary reaction. In some case, however, the potential curvature in the direction orthogonal to the reaction path changes from positive to negative, and the reaction path bifurcation occurs. In this project, a global reaction path map is generated for a small gold cluster, as an example, by anharmonic downward distortion following method and IRC calculation, and the condition and frequency at which a reaction path bifurcation occurs are investigated. It is shown that there always exists a transition state in the region close to the valley-ridge transition point. The dynamics effect and branching ratio are further analyzed by AIMD simulations, which leads to a proposal of a dynamical reaction picture.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 16KT0047
• Nonadiabatic transition in photochemical reactions studied by time-resolved spectroscopy of molecular orbitals
  Grants-in-Aid for Scientific Research
  01 Apr. 2015 - 31 Mar. 2018
  sekikawa taro; TAKETSUGU Tetsuya; IIKUBO Ryo; TENTAKU Tateharu; ARAKI Kotaro; ATOBE Ryunosuke
  Relaxation dynamics of 1,3-pentadiene(PD) and 2,5-dimethyl-2,4-hexadiene(DH) were investigated by time-resolved photoelectron spectroscopy to elucidate the effects of the steric hinderence or the mass by the methyl groups on the relaxation dynamics of the conjugated dienes.
  Our theoretical calculation reveals that the molecular structure of DH at a conical intersection is totally different from those of BD and PD, which might be attributable to the steric hinderence. Upon returning to the ground state, the stimulated vibrational modes in DH and PD are different because of the different structure at the conical intersections. This difference appears in the photoelectron specra.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 15H03702
• Theoretical study on excited-state dynamics with plural factors
  Grants-in-Aid for Scientific Research
  01 Apr. 2014 - 31 Mar. 2017
  Taketsugu Tetsuya; NAKAYAMA Akira
  For excited-reaction dynamics including nonadiabatic region, the spin-flip TDDFT is introduced with a tracking method to perform the first principles dynamics simulation. In collaboration with laser spectroscopic experiments, the reaction mechanism and dynamics of the photo-isomerization reaction of stilbene and its derivatives, as well as the excited state dynamics of 1,2-butadiene, are elucidated. The reaction quantum yield, the lifetime in the excited state, and molecular motion after deactivation are all well explained through the present theoretical simulations.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 26288001
• Ab initio simulation of matrix-isolation vibrational spectroscopy
  Grants-in-Aid for Scientific Research
  2011 - 2012
  TAKETSUGU Tetsuya; NORO Takeshi; NAKAYAMA Akira
  We have developed a computational scheme to investigate the vibrational shift of a target molecule embedded in noble-gas matrix environments in the framework of the mixed quantum-classical simulations. The high-level ab initio calculations were carried out to determine the interaction potential needed to construct the total potential of the system, and the Monte Carlo simulations were performed using this potential in order to obtain vibrational spectra in the presence of surrounding noble-gas atoms. The vibrational shifts of NgBeO (Ng=Ar, Xe) and HXeCl in various noble-gas matrices were investigated and the origin of the spectral shifts were discussed in detail. From this work, it was shown that the explicit treatment of the surrounding noble-gas atoms is essential to reproduce the experimentally observed vibrational shifts.
  Japan Society for the Promotion of Science, Grant-in-Aid for Challenging Exploratory Research, Hokkaido University, Principal investigator, Competitive research funding, 23655001
• A Theoretical Study on the catalytic activity of gold nanoparticles
  Grants-in-Aid for Scientific Research
  2010 - 2012
  LYALIN Andrey; TAKETSUGU Tetsuya
  Catalytic activity of small size-selected gold clusters for oxidation and hydrogen dissociation reactions has been studied theoretically using density functional theory. Cooperative effect in co-adsorption of C_2H_4 and O_2 on small gold clusters is found. It is demonstrated that co-adsorption of the reactant molecule can promote activation and dissociation of the molecular oxygen. The important role of the support effects on catalytic activity of gold clusters is studied. Two types of support are considered-the “inert” support of hexagonal boron nitride (h-BN) and the “active” support of rutile TiO_2(110). It is found that inert h-BN support can considerably affect catalytic activity of gold particles and modify barriers of chemical reactions catalyzed by gold. Electron-pushing mechanism of activation of the molecular O2 adsorbed on Au/h-BN is found. It is shown that h-BN support can be functionalized by N-doping and become catalytically active for oxygen reduction reaction. It is emonstrated that the active TiO_2 support considerably promotes H_2 dissociation on the supported gold clusters. It is shown theoretically that the catalytic activity of gold nanoparticles supported on the rutile TiO_2(110) surface is proportional to the length of the perimeter interface between the nanoparticle and the support.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (C), Hokkaido University, 22550001
• Theoretical development of ab initio reaction dynamics approach and generalized program code
  Grants-in-Aid for Scientific Research
  2009 - 2011
  TAKETSUGU Tetsuya; NORO Takeshi; NAKAYAMA Akira
  Ab initio molecular dynamics (AIMD) approach has been extended to treat nonadiabatic process and tunneling process, and has been applied to several significant reactions to clarify key factors in excited-state and tunneling dynamics, i.e., (1) non-adiabatic transition, (2) solvent effects, (3) quantum effects of nuclei, (4) branching ratio, (5) lifetime, and (6) reaction pathways.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, Principal investigator, Competitive research funding, 21350002
• 希ガスマトリックス効果を考慮した凝縮系振動スペクトルシミュレーションの理論開発
  科学研究費補助金(萌芽研究, 挑戦的萌芽研究)
  2008 - 2009
  武次 徹也; 野呂 武司; 中山 哲
  本研究では、量子化学計算手法を凝縮系のダイナミクスに実装し、不安定分子種の分光定数を測定する手段として長らく利用されてきた「希ガスマトリックス単離法」を理論的にシミュレートする方法論を開発することを目的として研究を進めてきた。あわせて、希ガスマトリックス分光法で測定された実験データの中に希ガス化合物に帰すべきものが含まれていないか、高精度理論計算に基づき調べている。本年度は(1)キセノンとグラフェンの相互作用に関する高精度計算、(2)Ar-PtCO、Ar-PdCOの高精度分光定数予測、(3)希ガスマトリックス振動スペクトルシミュレーションプログラムの開発とキセノンマトリックス中に単離されたXe-BeOの振動スペクトルへの適用を行った。ここでは、すでに論文で報告を行った(2)について概要を述べる。モノカルボニル化合物PtCO,PdCOについてはArマトリックス中で測定された振動数が報告されているが、特に変角振動の振動数について、理論計算で得られる調和振動数と実験値との間に二倍ほどのずれがあった。他研究グループの論文では、何らかの理由で実験では倍音が測定されたのでは、と議論されていたが、その根拠についてはフェルミ共鳴の可能性が指摘されるのみで、解決には至っていなかった。本研究では、ArがPtCO,PdCOに10kcal/molのオーダーの結合エネルギーで付着し、変角モードの振動数...
  文部科学省, 萌芽研究, 挑戦的萌芽研究, 北海道大学, Principal investigator, Competitive research funding, 20655001
• Ab initio Excited-State Reaction Dynamics and Its Applications to Photochemistry
  Grants-in-Aid for Scientific Research(特定領域研究)
  2006 - 2009
  Tetsuya TAKETSUGU; Takeshi NORO; Akira NAKAYAMA
  We have developed an ab initio molecular dynamics(AIMD)program code for excited-state processes, and applied it to several significant reactions to clarify key factors in excited-state dynamics, i.e., (1)non-adiabatic transition, (2)solvent effects, (3)spin-orbit coupling effects, (4)quantum effects of nuclei, (5)branching ratio, (6)lifetime, and (7)reaction pathways.
  Ministry of Education, Culture, Sports, Science and Technology, 特定領域研究, 北海道大学, Principal investigator, Competitive research funding, 18066001
• Ab initio molecular dynamics simulation of dissociative recombination reaction of interstellar molecules
  Grants-in-Aid for Scientific Research(基盤研究(B))
  2006 - 2008
  Tetsuya TAKETSUGU
  電子励起状態に適用可能な、Tullyの状態遷移アルゴリズムを実装したabinitio分子動力学プログラムを開発し、星間分子の解離性再結合反応HCNH+, H_3O^+, HD_2O^+, CH_3^+, (H_2O)_2H^+へと適用して、解離生成物の分岐比、動的反応経路、反応ダイナミクスの解明を行った。
  Ministry of Education, Culture, Sports, Science and Technology, 基盤研究(B), 北海道大学, Principal investigator, Competitive research funding, 18350001
• Asymmetric synthesis on the basis of conformation-control through cation-π interaction
  Grants-in-Aid for Scientific Research
  2005 - 2008
  YAMADA Shinji
  ピリジニウム環とアリール基との分子内カチオンーπ相互作用が様々な有機分子の立体配座制御に有効であることを見出し、置換ジヒドロピリジン類およびシクロプロパン類の立体選択的合成に有効であることを実証した. さらに、本相互作用を分子間に拡張することで、溶液および固相におけるアルケン類の[2+2]付加環化反応が、高い選択性でsynHT 体を与えることを見出し、カチオンーπ相互作用が分子間の立体選択的反応においても有効であることを明らかにした.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Ochanomizu University, 17350046
• 水分子クラスターにおけるトンネル効果の理論的研究
  科学研究費補助金(若手研究(B))
  2002 - 2003
  武次 徹也
  水分子二量体・三量体において有効分子対称群を考えると、最安定構造に対する同種核置換異性体はそれぞれ8個、48個あり、各異性体をつなぐ反応経路は二量体で3種類(acceptor tunneling, acceptor-donor interchange, donor tunneling)、三量体で2種類(single flip, bifurcation tunneling)あることがわかっている。各水分子クラスターにおけるトンネル効果を理論の立場から定量的に調べるため、MP2, CCSD(T)/aug-cc-pVXZ(X=D,T)レベルの電子状態計算により最安定構造および各反応の遷移状態構造を求め、結合エネルギー、活性化エネルギーを比較したところ、MP2/aug-cc-pVTZレベルで十分精度良い結果が得られることがわかった。対象とする系が分子間力である水素結合を伴う系であることを考慮して、結合エネルギーおよび分子構造についてはcounterpoise法による基底関数重ね合せ誤差(BSSE)の補正をした計算も行ったが、電子相関を考慮した方法においてはBSSEの補正はむしろ行わない方が基底関数の大きさに関して良い収斂が得られることがわかった。次に、各異性体をつなぐ反応に対し、MP2レベルで決定した固有反応経路をトンネル経路と近似し、半古典論に基づいてトンネル相互作用項の大きさをそ...
  文部科学省, 若手研究(B), お茶の水女子大学, Principal investigator, Competitive research funding, 14740325
• 内挿法によるabinitioポテンシャル曲面の生成とダイナミックスへの応用
  科学研究費補助金(特定領域研究(A))
  2000 - 2001
  武次 徹也
  本申請課題では、内挿法によるab initioポテンシャル曲面(PES)生成法の一般化を行い、動力学の諸問題に応用することを目的とした研究を行った。まず、1994年にCollinsらによって提案された修正Shepard内挿法に基づくPESの生成法を、デカルト座標に基づいて定式化することにより一般の多原子分子系に適用できる形に拡張することに成功した。本方法を、(1)マロンアルデヒドの分子内水素移動反応・蟻酸二量体の分子間二重水素移動反応における多次元トンネル動力学、(2)水、ホルムアルデヒド分子の振動-回転エネルギー準位の予測、の2つの動力学の問題に応用した。以下順次成果を述べる:(1)反応経路が大きく曲がるためにトンネル効果を定量的に見積もることが困難な系として知られているマロンアルデヒドの分子内水素移動反応に対して全21自由度を含んだab initioポテンシャル曲面を作成し、Millerのモデルを適用してトンネル効果によるエネルギー分裂を評価したところ、実験値を非常に精度よく再現することができた。蟻酸二量体の分子間二重水素移動反応(24自由度)についても、同様にしてPESを作成し、simulationを行うことにより、トンネル分裂を定量的に見積もることができた。(2)振動-回転エネルギー準位を理論予測する振動SCF法にdirectに電子状態計算を組み合わせたdirect ...
  文部科学省, 特定領域研究(A), お茶の水女子大学, Principal investigator, Competitive research funding, 12042228
• Development of ab initio molecular orbital program for large-scale molecular systems
  Grants-in-Aid for Scientific Research
  1998 - 2000
  HIRAO Kimihiko; TAKETSUGU Tetsuya; NAKAJIMA Takahito; NAKANO Haruyuki
  The aim of this research project is to develop an ab initio molecular orbital program that can determine the electronic structure of large-scale systems, including more than 1000 atoms, with high accuracy and high performance. To achieve this aim, both pure theoretical and practical aspects are necessary : development of new methods in theory and new technology in algorithm and program. In the former aspect, our focus was particularly on the development of (1) new ab initio molecular orbital theory, especially multireference-based methods, (2) molecular orbital theory including relativistic effects, and (3) exchange and correlation functional in density functional theory ; and we succeeded in the development of MRMP with localized orbitals, MRMP with CASCI reference, quasi-complete active space SCF method, QCAS-SCF reference QDPT, RESC, third-order Douglas-Kroll method, highly efficient scheme of Dirac-Hatree-Fock and Dirac-Kohn-Sham methods, relativistic model potentials, parameter-free exchange functional, one-parameter-progressive correlation functional. In the latter aspect, we developed a molecular integral program, Spherica, based on high-performance integral method, and the programs of Dirac-Hatree-Fock and Dirac-Kohn-Sham methods based on the above-mentioned schemes. These are not programs simply coded according to conventional computational techniques, but programs obtained by the use of new technologies found after optimization of every computational scheme including molecular integrals.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B)., The University of Tokyo, 10555298
• 多原子分子反応におけるトンネル経路モデルの開発
  科学研究費補助金(奨励研究(A))
  1998 - 1999
  武次 徹也
  本課題では多原子分子反応にも適用可能な半古典トンネルモデルの定式化を目的として研究を行った。初年度は、Truhlarらが2次元共線形に対して定式化した「最小作用原理に基づくトンネル経路モデル」の多次元系への一般化を試みた。彼らのモデルでは、経路に沿った虚の作用積分を最小にするために最小エネルギー経路(MEP)と最短移動経路(LMP)の重み付き平均として一群の経路を定義し、その重みを変分パラメーターとして作用積分の最小値を与える経路をトンネル経路とする。我々は、反応経路の接線・曲率ベクトルで決まる2次元の座標空間を局所的反応平面と定義してMEPに沿った変化を調べ、経路が大きく曲がる領域で反応平面は安定であること、MEP全体を反応平面のねじれに基づきいくつかの領域に分割できることを見い出した。この幾何学的性質を利用し、まず反応経路をねじれに基づいて安定な反応平面を持ついくつかの断片に分割し、各領域で局所的なLMPとMEPとを加重平均して一群の経路を発生させ、経路群の中で最小作用を与える経路をその領域におけるトンネル経路とし、各領域の局所トンネル経路を合成して全トンネル経路とする方法を提案した。この方法をheavy-light-heavy系であるNH_3+OH→NH_2+H_2Oに適用し、MEPより大きなトンネル確率を与える最適なトンネル経路を決定することが出来た。また、本トンネル...
  文部科学省, 奨励研究(A), 東京大学->お茶の水女子大学, Principal investigator, Competitive research funding, 10740266
• Theoretical Study on the Photoreactions of Biological Compounds
  Grants-in-Aid for Scientific Research
  1997 - 1998
  HIRAO Kimihiko; TAKETSUGU Tetsuya; NAKANO Haruyuki
  Our Multireference Moller-Plesset (MRMP) theory is an extension of the closed-shell single reference MP method and has been successfully applied to numerous chemical and spectroscopic problems. MRMP has established through this study as an efficient technique for treating both dynamical and nondynamical correlation effects. MRMP was applied to the study of the valence pi*pi^* excited states of polyenes, polyacenes, and porphyrins. MRMP satisfactorily describes the ordering of low-lying valence pi*pi^* excited states for alternant hydrocarbons. MRMP predicts the valence excitation energies with an accuracy of 0.2 eV or better. The MRMP approach with the alternant pairing properties has proved to be of great value in understanding and predicting the experimental data of the alternant hydrocarbons. The conclusion derived in this study is to some extent transferable and thus provides a reasonable basis for a description of the excited states of other larger polyenes, polyacenes and porphyrins. We have also proposed a complete active space valence bond (CASVB) method. A CASVB wave function can be obtained simply by transforming a canonical CASSCF function and readily interpreted in terms of the well-known classical VB resonance structures. The CASVB affords a clear view of the wave functions for the various states. In addition, we have proposed several new theory and concepts : MRMP in the extended basis function space (EBS), relativistic MRMP with a new relativistic scheme by eliminating small-component (RESC) of the four-component Dirac equation. EBS-MRMP is a theory based on a concept of different bases for different correlation effects. The new RESC-scheme is a very promising alternative to the Dirac method. We have also proposed a new simplified Colle-Salvetti-type correlation functional called OP in density functional theory. OP includes only one-parameter and no adjusted functional constant. OP satisfies all the necessary conditions of the exact correlation functional. OP is proved to give more accurate correlation energies for atoms and equivalent chemical properties for G2 set of molecules.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), The University of Tokyo, 09450314
• 固体表面での吸着反応に関する理論的研究
  科学研究費助成事業
  1997 - 1997
  平尾 公彦; 武次 徹也; 中野 晴之; 山下 晃一
  平成9年度は、H交換ゼオライト触媒上のメタノール->ガソリン転化反応(MTG法)、Cu交換ゼオライト触媒上のNO分解反応、金属表面上のメタンの光分解反応に関して研究を行った。
  MTG法に関しては、我々は、特に多くの異論の唱えられてきた、炭素-炭素結合生成のメカニズムに着目し、量子化学計算に基づき反応経路の決定を試みた。その結果、ゼオライト表面上のメトキシ基とメタノールとの間の反応により、ホルムアルデヒドとメタン、エタノールを経て、エチレンに至る反応経路が最も優位であるとの結果を得た。この反応経路は生成化合物の推移などに関する実験観測との整合性も高く、このことに鑑みて実際に可能な経路の一つであろうと結論した。NO分解反応に関しても、反応経路の決定を行い、ゼオライトの触媒効果に関して考察した。銅イオンに比べて銅原子上では反応障壁が非常に低いことが計算の結果明らかとなり、ゼオライトの触媒効果が、原子状の銅を分散担持することに有るのでは無いかと示唆することができた。メタンの光分解反応に関しては、Pt,Ni,Pd金属表面のモデルとして原子10個程度のクラスターを用いて励起状態を計算し、それぞれの状態の分子軌道論理論的抽象およびポテンシャルエネルギー曲面の解析を行った。メタンの結合解離を導く励起状態が、基底状態の平衡構造においては、金属表面ではなく局所的にメタンを励起したものであることに基づき、光分解が直接励起によるものであることを明らかにした。またこの状態が金属表面との相互作用によりエネルギー的に大きく安定化することなどの実験事実を説明できることも確認できた。
  日本学術振興会, 重点領域研究, 東京大学, 09218213
• Time-dependent Approach in Theoretical Chemistry
  Grants-in-Aid for Scientific Research
  1996 - 1997
  HIRAO Kimihiko; TAKETSUGU Tetsuya; NAKANO Haruyuki; YAMASHITA Koichi; NICHOLAS C.Handy; LORENZ S.Cederbaum
  The purpose of the present project is developing new time-dependent approaches in the electronic correlation and electron-nuclear interaction problems. It is an urgent problem to develop theories which can treat the time-dependent events quantitatively, as well as methods for large-scale systems which are applicable to the molecular design and chemical reaction design. Our focus was, therefore, on the development of new theories and methods and their applications to chemical phenomena : a method for constructing potential energy surfaces, which is crucial for chemical reaction, accurately and efficiently ; a reaction path model based on dynamic reaction path on the potential surfaces ; wave packet method including electron-nuclear interaction ; and the application of these methods to the chemical reactions.
  A new time-dependent density functional method and an analytic energy gradient method including electron correlation were formulated, and their program code were developed by collaborating Professor Handy. A theory for tunneling in multidimensional potential surfaces was also formulated and applied to polyatomic chemical reactions. An efficient diagonalization method of large Hamiltonian matrices was developed by collaborating Professor Carbo. Numerical tests were performed to verify the accuracy and efficiency of the new algorithm. A wave packet method including electron-nuclear interaction and a method for constructing potential energy surfaces based on the dynamic reaction path were discussed with Professor Cederbaum. The methods mentioned above were applied to the studies of several chemical phenomena such as dissociation mechanisms of polyatomic molecules and fluorescence of radicals.
  Japan Society for the Promotion of Science, Grant-in-Aid for international Scientific Research, The University of Tokyo, 08044063
• 多自由度トンネル反応の素過程と波束ダイナミックス
  科学研究費助成事業
  1996 - 1996
  山下 晃一; 武次 徹也
  ポテンシャル障壁のトンネルは化学反応における重要な量子効果の一つである。特に低温域での化学反応の機構、速度、準安定状態の崩壊、分子分光スペクトルの解析等にトンネル現象の理解が不可欠である。そこで本研究では、(1)化学反応過程を反応座標モデルで記述し、経路積分法と量子波束法を導入した多自由度系での量子力学的計算法を新たに開発し、トンネル確率への多自由度の影響、トンネル領域における波束ダイナミックスとトンネル時間に対する多自由度の影響を明らかにすることを目的とした。また(2)量子クラスターのシミュレーションに必要なモンテ・カルロ経路積分法を新たに開発し、極低温凝縮系のトンネル現象の機構を明らかにすることを目的とした。凝縮系の分子動力学計算やモンテ・カルロ計算は、これまで一般的に古典系に対するものが普通であった。ところが量子クラスター、さらには超流動相ヘリウムの場合には多自由度系での量子力学的計算を行う必要が生じる。絶対ゼロ度での量子シミュレーションには量子モンテカルロ法などが用いられるが、ここでは有限温度の量子クラスターのシミュレーションに必要なモンテ・カルロ経路積分法を新たに開発した。具体的応用として、最近、理研の笠井、高見らが極低温液体ヘリウム中にナフタレン分子を注入することに成功し、電子スペクトルを観測した系を取り上げ、ナフタレン分子をドープした量子ヘリウムクラスターの構造を理論的に検討した。
  日本学術振興会, 重点領域研究, 東京大学, 08240212
• Pt表面でのNO吸着特性と直接分解反応に関する理論的研究
  科学研究費助成事業
  1996 - 1996
  平尾 公彦; 武次 徹也; 中野 晴之; 山下 晃一
  本年度は、ab initio分子軌道法と密度汎関数法を併用し、Pt(111)表面におけるメタンの光解離反応、H型ゼオライト上の水分子の吸着およびプロトン交換反応、に対して理論的研究を行った。気相のメタンを解離させるには185nm以下の波長の光が必要がであるが、最近、Pt表面に物理吸着したメタンは193nmの光を照射することによってメチルラジカルと水素原子に解離することが実験により見い出された。本研究では、Pt表面をクラスターで近似し、密度汎函数法およびCASSCF法による計算を行なって、(1)メタンはontop構造で表面から3.00Å離れて物理吸着すること、(2)単分子の励起状態から約3eVシフトしたcharge transfer型の励起状態がCH_3+Hへの解離を引き起こすこと、を明らかにした。今後は、同族のPd,Ni表面について同様の計算を行ない、反応性の違いを比較する予定である。ゼオライトの問題では、そのプロトン供与性による触媒能に関連し、H型ゼオライト上の活性点と水分子のプロトン交換反応を含む吸着状態を、特にオキソニュウム化合物の存否の観点から調べた。ゼオライト骨格はクラスターによってモデル化し、ゼオライト-H_2Oの錯体に対してHartree-Fock計算により2個の吸着構造(プロトン供与型および水素結合型)を求め、電子相関を考慮した2次摂動法計算によりこれらがほぼ等しい吸着エネルギーを与えることを明らかにした。一方で、平衡構造における調和振動数と実験の赤外吸収位置との比較においてプロトン供与型錯体では〜3600cm^<-1>の実測値に対応する計算値が現われない点で大きく異なることから、水素結合型の錯体が優位に形成されているとの結果を得た。このことは、実験によって示唆されている水素結合型の吸着を支持するものである。
  日本学術振興会, 重点領域研究, 東京大学, 08232218
• 希土類錯体の電子状態や結合に関与するf-電子の役割りの理論的解明
  科学研究費助成事業
  1996 - 1996
  平尾 公彦; 武次 徹也; 中野 晴之
  本研究課題では、希土類錯体の電子状態や結合様式における4f電子の果たす役割を理論的に解明する事を目的とし、ab initio分子軌道法による理論計算を用いて諸問題に取り組んでいる。一連のランタニド三塩化物LnCl_3に対する理論計算により、f軌道への電子のつまり方に関して、これまでのs,p,d軌道のみを含む分子系の常識とは反した興味深い現象が見いだしてきた。7つのf軌道には電子はフント則に従って1つずつ詰まっていくが、7つのf軌道のすべてに電子が一つずつ詰まった後、8つ目の電子からは軌道エネルギーの高いf軌道から順に詰まっていく。本年度は錯体中の4f軌道の擬縮退の状態を解明し、それに基づいて上記の現象の理論的な解明に成功した。さらに、計算に際して配位子の基底関数におけるd分極関数の効果を確認し、その必要性を示唆した。加えて現在、ランタニド二核錯体Ln_2F_6の計算を行い、2組のf軌道の相互作用によるf軌道の分裂の様子や、それによってf軌道が結合へ参加する可能性、さらにf軌道が外部の分子に及ぼす化学的な影響の理論的解明を試みている。一方で、近年、O_h対称の構造をもつ6フッ化アニオンが安定に存在することが予測されていることに着目し、希土類多価負イオンLnF_6^(n=2,3)の存在を理論的に検討している。まず、すべての希土類元素に対してLnF_6^はOh対称の安定な分子構造を持ち、電子構造はLn=Gdではn=3、それ以外ではn=2で最安定であることを確認した。次いで、解離反応LnF_6^→LnF_5^<(n-1)>+F^-の反応障壁、反応熱を求めて、LnF_6^の安定性を考察した。一般には多価負イオンは解離に際してクーロンエネルギーの放出による発熱をともなう準安定分子であることが知られており、n=3の場合にはその反応障壁は10kcal/mol程度である。一方n=2の場合には、原系が生成系より安定に存在することを明らかにした。
  日本学術振興会, 重点領域研究, 東京大学, 08220213
• 励起状態の反応ダイナミクス
  Competitive research funding
• Direct dynamics on electronic excited states
  Competitive research funding