Publication

Research Article 

1. Mapping the Product-Dividing Boundary from a Valley-Ridge Inflection to the Product-Connecting Transition State in Substituent-Controlled Bifurcating Reactions
   Jidai Suzuki, Tatsuhiro Nakanishi, Ryuto Kambara, Yuriko Ono, Takuro Tsutsumi, Tetsuya Taketsugu,
   Journal of Chemical Theory and Computation, 2026, 22, 7274-7285. (DOI: 10.1021/acs.jctc.6c01022) (Selected as Supplementary Journal Cover)

2. 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, 2026, in press. (DOI: 10.1039/d6cp01610c) (Selected as Outside Front Cover)

3. Lower Critical Solution Temperature-Type Phase Behavior of Poly(N-isopropylacrylamide) in Nonaqueous Organic Solvents
   Koki Takasu, Akari Sugano, Masami Naya, Takuro Tsutsumi, Keitaro Matsuoka, Kazuki Sada,
   Macromolecules, 2026, 59, 7382-7391. (DOI: 10.1021/acs.macromol.6c00602) (Selected as Front Cover)

4. Beyond Diagnosis: Transdiagnostic Cognitive Subgroups in Mood Disorders Linked to Work‐Related Disability
   Ryo Sawagashira, Takuro Tsutsumi, Hayato Watanabe, Atsuhito Toyomaki, Ryo Okubo, Naoki Hashimoto, Takahiro A. Kato,
   Neuropsychopharmacology Reports, 2026, 46, e70116. (DOI: 10.1002/npr2.70116)

5. 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, 2025, 163, 224303. (DOI: 10.1063/5.0300477)

6. 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 2025, 16, 5373-5380. (DOI: 10.1021/acs.jpclett.5c00785)

7. 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, 2025, 46, e70101. (DOI: 10.1002/jcc.70101)

8. Dynamics of Doubly Ionized OCS Molecules and Hidden Reaction Pathways
   Ryuto Kambara, Takuro Tsutsumi, Kenji Furuya, Tetsuya Taketsugu,
   Journal of Computer Chemistry, Japan, 2025, 24, 5-9.

9. 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, 2024, 20, 10931-10941. (DOI: 10.1021/acs.jctc.4c01072)

10. 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, 2024, 161, 154103. (DOI: 10.1063/5.0230618)

11. 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, 2024, 16, 22-27. (DOI: 10.1038/s41557-023-01397-6) (Selected as Front Cover, RIKEN Press Release, Hokkaido Univ. Press Release)

12. Ab initio molecular dynamics study of intersystem crossing dynamics for <scp>MH₂</scp> (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, 2023, 45, 552-562. (DOI: 10.1002/jcc.27271)

13. 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, 2023, 1–13. (DOI: 10.1002/jcc.27204)

14. Multi-state Energy Landscape for Photoreaction of Stilbene and Dimethyl-stilbene
    Takuro Tsutsumi, Yuriko Ono, Tetsuya Taketsugu,
    Journal of Chemical Theory and Computation, 2022, 18, 7483–7495. (DOI: 10.1021/acs.jctc.2c00560) (Selected as Supplementary Journal Cover)

15. 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, 2022, 806, 140008-140008. (DOI: 10.1016/j.cplett.2022.140008)

16. 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, 2023, 44, 93–104. (DOI: 10.1002/jcc.27017)

17. 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, 2022, 2, 388–398. (DOI: 10.1021/acsphyschemau.2c00012) (Selected as Front Cover)

18. Extension of natural reaction orbital approach to multiconfigurational wavefunctions
    Shuichi Ebisawa, Takuro Tsutsumi, Tetsuya Taketsugu,
    The Journal of Chemical Physics, 2022, 157, 084118-084118. (DOI: 10.1063/5.0098230)

19. 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, 2022, 24, 3532-3545. (DOI: 10.1039/d1cp04491e) (Selected as 2021 PCCP HOT Articles, Inside Front Cover)

20. One-to-one correspondence between reaction pathways and reactive orbitals
    Masatoshi Hasebe, Takuro Tsutsumi, Tetsuya Taketsugu, Takao Tsuneda,
    Journal of Chemical Theory and Computation, 2021, 17, 6901-6909. (DOI: 10.1021/acs.jctc.1c00693)

21. 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 (Special issue: Ultrafast Science: Dynamics from Experiment and Theory), 2021, 54, 174004.  (DOI: 10.1088/1361-6455/ac274c)

22. 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, 2021, 12, 674-679. (DOI: 10.1021/acs.jpclett.0c03297) (Hokkaido Univ. Press Release, Featured in Nikkan Kogyo Shimbun (日刊工業新聞))

23. Geometric analysis of anharmonic downward distortion following paths
    Shuichi Ebisawa, Takuro Tsutsumi, Tetsuya Taketsugu,
    Journal of Computational Chemistry, 2020, 42, 27-39. (DOI: 10.1002/jcc.26430) (Selected as Front Cover)

24. 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, 2020, 16, 4029-4037. (DOI: 10.1021/acs.jctc.0c00018) (Selected as Supplementary Cover Art)

25. 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, 2018, 515, 564-571. (DOI: 10.1016/j.chemphys.2018.08.017)

26. 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, 2018, 14, 4263-4270. (DOI: 10.1021/acs.jctc.8b00176)

27. 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,  2018, 20, 1364-1372. (DOI: 10.1039/c7cp06528k) (Selected as 2018 PCCP HOT Articles)

Review Articles

1. Reaction Space Projector (ReSPer) for Visualizing Dynamic Reaction Routes Based on Reduced-Dimension Space
   Takuro Tsutsumi, Yuriko Ono, Tetsuya Taketsugu,
   Topics in Current Chemistry, 2022, 380, 19. (DOI: 10.1007/s41061-022-00377-7)

2. Visualization of reaction route map and dynamical trajectory in reduced dimension
   Takuro Tsutsumi, Yuriko Ono, Tetsuya Taketsugu,
   Chemical Communications, 2021, 57, 11734-11750. (DOI: 10.1039/d1cc04667e) (Selected as Front cover)

Books

1. 密度汎関数法による量子化学計算
   常田貴夫, 武次徹也（編著）
   講談社 (2025)　ISBN: 9784065396780
   堤 拓朗，武次徹也（分担） 第3章 3.3「反応ダイナミクス」　担当
   堤 拓朗，和田 諒，武次徹也（分担） 第4章 4.4「励起状態反応解析」、4.5「励起状態ダイナミクス」担当

2. Ab Initio Molecular Dynamics Analysis Based on Reduced-Dimensionality Reaction Route Map
   Takuro Tsutsumi,
   Springer Singapore, 2023. (ISBN:9789819973217)

3. Reaction Space Projector (ReSPer) for Visualizing Dynamic Reaction Routes Based on Reduced-Dimension Space
   Takuro Tsutsumi, Yuriko Ono, Tetsuya Taketsugu,
   Springer International Publishing, 2022, 55-77. (ISBN: 9783031076572)
   (Role: Contributor, Book title: New Horizons in Computational Chemistry Software)

4. On-the-Fly Excited-State Molecular Dynamics Study Based on Spin-Flip Time-Dependent Density Functional Theory Approach: Photo-Branching Reaction of Stilbene and Stilbene Derivatives
   Tetsuya Taketsugu, Takuro Tsutsumi, Yu Harabuchi, Takao Tsuneda,
   Jenny Stanford Publishing Pte. Ltd., 2022. (ISBN: 9789814968423)
   (Role: Contributor, Book title: Time-Dependent Density Functional Theory: Nonadiabatic Molecular Dynamics)

Misc.

1. 奨励賞受賞寄稿「低次元反応空間に基づく反応動力学解析法の開発と応用」
   堤 拓朗, 理論化学会誌『フロンティア』 (2026)　（受賞寄稿）（2026年第2号へ掲載予定）

2. 次元縮約に基づく反応空間投影法：反応動力学解析へのアプローチ
   堤 拓朗,  理論化学会誌「フロンティア」 5(2) 110-121 (2023年4月)

3. Extension of Natural Reaction Orbital Approach to Multiconfigurational Wavefunctions
   Shuichi Ebisawa, Takuro Tsutsumi, Tetsuya Taketsugu,
   Chemrxiv, 2022. (DOI: 10.26434/chemrxiv-2022-gl6hq)

4. Natural reaction orbitals
   Suichi Ebisawa, Msatoshi Hasebe, Takuro Tsutsumi, Takao Tsuneda, Tetsuya Taketsugu
   Chemrxiv, 2021. (DOI: 10.33774/chemrxiv-2021-l5pck)

5. 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,
   in Conference on Lasers and Electro-Optics, J. Kang, S. Tomasulo, I. Ilev, D. Müller, N. Litchinitser, S. Polyakov, V. Podolskiy, J. Nunn, C. Dorrer, T. Fortier, Q. Gan, and C. Saraceno, eds., OSA Technical Digest, 2021, (Optica Publishing Group), paper FTu4J.3. (DOI: 10.1364/cleo_qels.2021.ftu4j.3)

6. 沖縄科学技術大学院大学サイエンスフェスタでの実験教室出展報告：紙デバイスを用いたpH測定実験
   愉 彦樺,  小松 雄士,  文野 優華,  堤 拓朗,  小川 雄大,
   科学技術コミュニケーション, 2020, 26 17-28.

7. 優秀ポスター賞受賞寄稿「多次元データ縮約法による動的反応経路の可視化」
   堤 拓朗,  理論化学会誌 フロンティア 2(1) 21-22 (2020年1月)

8. 優秀講演賞受賞寄稿「静的反応経路網に基づくAIMD古典軌道解析」
   堤 拓朗, 理論化学会誌 フロンティア 1(1) 19-21 (2019年1月)

Computer Programs

1. T. Tsutsumi, K. Oda, J. Sakugawa, Y. Minegishi, A. Fujita, K. Iwata, R. Kambara, Y. Harabuchi, Y. Ono, T. Taketsugu, SPPR program, 2019-, Hokkaido University: Sapporo, Japan.

2. T. Tsutsumi, L. Qu, K. Mataki, Y. Ono, T. Taketsugu, Reaction Space Projector (ReSPer) program, 2018-, Hokkaido University: Sapporo, Japan.

3. Y. Harabuchi, M. Okai, R. Yamamoto, T. Tsutsumi, Y. Ono, T. Taketsugu, SPPR program, 2014-2018, Hokkaido University: Sapporo, Japan.