Updated on 2024/10/06

写真a

 
NISHIMURA, Yoshifumi
 
Affiliation
Faculty of Science and Engineering, Waseda Research Institute for Science and Engineering
Job title
Junior Researcher(Assistant Professor)
Degree
博士(理学) ( 名古屋大学 )

Research Experience

  • 2018.04
    -
    Now

    Tokyo University of Science   Faculty of Science, Division 1, Applied Chemistry

  • 2018.04
    -
    Now

    Waseda University   Waseda Research Institute for Science and Engineering   Junior Researcher (Assistant Professor)

  • 2016.04
    -
    2018.03

    Waseda University   Research Institute for Science and Engineering   Junior Researcher

  • 2014.06
    -
    2016.03

    Institute for Molecular Science   Department of Theoretical and Computational Molecular Science   Project Researcher

  • 2013.05
    -
    2014.05

    National Chiao Tung University   Department of Applied Chemistry   Postdoctoral Fellow

Education Background

  • 2008.04
    -
    2013.03

    Nagoya University   Graduate School of Science   Department of Chemistry  

  • 2004.04
    -
    2008.03

    Nagoya University   School of Science   Department of Chemistry  

Committee Memberships

  • 2016
    -
     

    第19回理論化学討論会  実行委員

Professional Memberships

  •  
     
     

    Japan Society of Theoretical Chemistry

  •  
     
     

    THE CHEMICAL SOCIETY OF JAPAN

  •  
     
     

    分子シミュレーション学会

  •  
     
     

    分子科学会

Research Areas

  • Fundamental physical chemistry

Research Interests

  • Theoretical Chemistry

  • Quantum Chemistry

  • Computational Chemistry

Awards

  • CSJ Presentation Award

    2017.03   Chemical Society of Japan  

    Winner: NISHIMURA, Yoshifumi

  • President's Award

    2008.03   Nagoya University  

    Winner: NISHIMURA, Yoshifumi

 

Papers

  • Enabling large-scale quantum path integral molecular dynamics simulations through the integration of Dcdftbmd and i-PI codes

    Yoshifumi Nishimura, Hiromi Nakai

    The Journal of Chemical Physics   158 ( 16 ) 164101 - 164101  2023.04  [Refereed]

     View Summary

    A large-scale quantum chemical calculation program, Dcdftbmd, was integrated with a Python-based advanced atomistic simulation program, i-PI. The implementation of a client–server model enabled hierarchical parallelization with respect to replicas and force evaluations. The established framework demonstrated that quantum path integral molecular dynamics simulations can be executed with high efficiency for systems consisting of a few tens of replicas and containing thousands of atoms. The application of the framework to bulk water systems, with and without an excess proton, demonstrated that nuclear quantum effects are significant for intra- and inter-molecular structural properties, including oxygen–hydrogen bond distance and radial distribution function around the hydrated excess proton.

    DOI

    Scopus

  • Species-selective nanoreactor molecular dynamics simulations based on linear-scaling tight-binding quantum chemical calculations

    Yoshifumi Nishimura, Hiromi Nakai

    The Journal of Chemical Physics   158 ( 5 ) 054106 - 054106  2023.02  [Refereed]

     View Summary

    Here, extensions to quantum chemical nanoreactor molecular dynamics simulations for discovering complex reactive events are presented. The species-selective algorithm, where the nanoreactor effectively works for the selected desired reactants, was introduced to the original scheme. Moreover, for efficient simulations of large model systems with the modified approach, the divide-and-conquer linear-scaling density functional tight-binding method was exploited. Two illustrative applications of the polymerization of propylene and cyclopropane mixtures and the aggregation of sodium chloride from aqueous solutions indicate that species-selective quantum chemical nanoreactor molecular dynamics is a promising method to accelerate the sampling of multicomponent chemical processes proceeding under relatively mild conditions.

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  • Divide-and-Conquer Linear-Scaling Quantum Chemical Computations

    Hiromi Nakai, Masato Kobayashi, Takeshi Yoshikawa, Junji Seino, Yasuhiro Ikabata, Yoshifumi Nishimura

    The Journal of Physical Chemistry A   127 ( 3 ) 589 - 618  2023.01  [Refereed]

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    14
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  • Quantum-Mechanical Molecular Dynamics Simulations on Secondary Proton Transfer in Bacteriorhodopsin Using Realistic Models

    Hiromi Nakai, Toshiaki Takemura, Junichi Ono, Yoshifumi Nishimura

    The Journal of Physical Chemistry B   125 ( 39 ) 10947 - 10963  2021.10  [Refereed]

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    10
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  • Quantum Chemical Calculations for up to One Hundred Million Atoms Using Dcdftbmd Code on Supercomputer Fugaku

    Yoshifumi Nishimura, Hiromi Nakai

    Chemistry Letters   50 ( 8 ) 1546 - 1550  2021.08  [Refereed]

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    8
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  • Is Oxygen Diffusion Faster in Bulk CeO2 or on a (111)-CeO2 Surface? A Theoretical Study

    Aditya Wibawa Sakti, Chien-Pin Chou, Yoshifumi Nishimura, Hiromi Nakai

    Chemistry Letters   50 ( 4 ) 568 - 571  2021.04  [Refereed]

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    4
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  • Density-Functional Tight-Binding Parameters for Bulk Zirconium: A Case Study for Repulsive Potentials

    Aulia Sukma Hutama, Chien-pin Chou, Yoshifumi Nishimura, Henryk A. Witek, Stephan Irle

    The Journal of Physical Chemistry A   125 ( 10 ) 2184 - 2196  2021.03  [Refereed]

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  • Hydroxide Ion Carrier for Proton Pumps in Bacteriorhodopsin: Primary Proton Transfer

    Junichi Ono, Minori Imai, Yoshifumi Nishimura, Hiromi Nakai

    JOURNAL OF PHYSICAL CHEMISTRY B   124 ( 39 ) 8524 - 8539  2020.10  [Refereed]

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    15
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  • Hierarchical parallelization of divide‐and‐conquer density functional tight‐binding molecular dynamics and metadynamics simulations

    Yoshifumi Nishimura, Hiromi Nakai

    Journal of Computational Chemistry   41 ( 19 ) 1759 - 1772  2020.07  [Refereed]  [International journal]

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    10
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  • Spin-flip approach within time-dependent density functional tight-binding method: Theory and applications

    Mayu Inamori, Takeshi Yoshikawa, Yasuhiro Ikabata, Yoshifumi Nishimura, Hiromi Nakai

    Journal of Computational Chemistry   41 ( 16 ) 1538 - 1548  2020.03  [Refereed]

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    12
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  • Large-Scale Molecular Dynamics Simulation for Ground and Excited States Based on Divide-and-Conquer Long-Range Corrected Density-Functional Tight-Binding Method

    Nana Komoto, Takeshi Yoshikawa, Yoshifumi Nishimura, Hiromi Nakai

    Journal of Chemical Theory and Computation   16 ( 4 ) 2369 - 2378  2020.03  [Refereed]  [International journal]

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    23
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  • Confined water-mediated high proton conduction in hydrophobic channel of a synthetic nanotube

    Ken-ichi Otake, Kazuya Otsubo, Tokutaro Komatsu, Shun Dekura, Jared M. Taylor, Ryuichi Ikeda, Kunihisa Sugimoto, Akihiko Fujiwara, Chien-Pin Chou, Aditya Wibawa Sakti, Yoshifumi Nishimura, Hiromi Nakai, Hiroshi Kitagawa

    Nature Communications   11 ( 1 ) 843  2020.02  [Refereed]

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    124
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  • Recent advances in quantum‐mechanical molecular dynamics simulations of proton transfer mechanism in various water‐based environments

    Aditya W. Sakti, Yoshifumi Nishimura, Hiromi Nakai

    WIREs Computational Molecular Science   10 ( 1 ) e1419  2020.01  [Refereed]

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    13
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  • Cover Image, Volume 10, Issue 1

    Aditya W. Sakti, Yoshifumi Nishimura, Hiromi Nakai

    WIREs Computational Molecular Science   10 ( 1 )  2020.01  [Refereed]

    DOI

  • GPU‐Accelerated Large‐Scale Excited‐State Simulation Based on Divide‐and‐Conquer Time‐Dependent Density‐Functional Tight‐Binding

    Takeshi Yoshikawa, Nana Komoto, Yoshifumi Nishimura, Hiromi Nakai

    Journal of Computational Chemistry   40 ( 31 ) 2778 - 2786  2019.12  [Refereed]

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    23
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  • Sodium‐ and Potassium‐Hydrate Melts Containing Asymmetric Imide Anions for High‐Voltage Aqueous Batteries

    Qifeng Zheng, Shota Miura, Kasumi Miyazaki, Seongjae Ko, Eriko Watanabe, Masaki Okoshi, Chien‐Pin Chou, Yoshifumi Nishimura, Hiromi Nakai, Takeshi Kamiya, Tsunetoshi Honda, Jun Akikusa, Yuki Yamada, Atsuo Yamada

    Angewandte Chemie   131 ( 40 ) 14340 - 14345  2019.10  [Refereed]

    DOI

  • 分割統治型密度汎関数強束縛分子動力学(DC-DFTB-MD)法による表面反応シミュレーション:Pt(111)表面上のプロトン拡散

    中井 浩巳, 西村 好史, Aditya Wibawa Sakti, Tanabat Mudchimo, 周 建斌

    表面と真空   62 ( 8 ) 486 - 491  2019.08  [Refereed]

    DOI

  • Sodium‐ and potassium‐hydrate melts containing asymmetric imide anions for high‐voltage aqueous batteries

    Qifeng Zheng, Shota Miura, Kasumi Miyazaki, Seongjae Ko, Eriko Watanabe, Masaki Okoshi, Chien-Pin Chou, Yoshifumi Nishimura, Hiromi Nakai, Takeshi Kamiya, Tsunetoshi Honda, Jun Akikusa, Yuki Yamada, Atsuo Yamada

    Angewandte Chemie International Edition   58 ( 40 ) 14202 - 14207  2019.07  [Refereed]

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    89
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  • D cdftbmd : Divide‐and‐Conquer Density Functional Tight‐Binding Program for Huge‐System Quantum Mechanical Molecular Dynamics Simulations

    Yoshifumi Nishimura, Hiromi Nakai

    Journal of Computational Chemistry   40 ( 15 ) 1538 - 1549  2019.06  [Refereed]

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    54
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  • Development of Large-Scale Excited-State Calculations Based on the Divide-and-Conquer Time-Dependent Density Functional Tight-Binding Method

    Nana Komoto, Takeshi Yoshikawa, Junichi Ono, Yoshifumi Nishimura, Hiromi Nakai

    Journal of Chemical Theory and Computation   15 ( 3 ) 1719 - 1727  2019.03  [Refereed]

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    17
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  • Development of Divide-and-Conquer Density-Functional Tight-Binding Method for Theoretical Research on Li-Ion Battery

    Chien-Pin Chou, Aditya Wibawa Sakti, Yoshifumi Nishimura, Hiromi Nakai

    The Chemical Record   19 ( 4 ) 746 - 757  2018.11  [Refereed]

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    12
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  • Density-Functional Tight-Binding Molecular Dynamics Simulations of Excess Proton Diffusion in Ice Ih, Ice Ic, Ice III, and Melted Ice VI Phases

    Aditya Wibawa Sakti, Yoshifumi Nishimura, Chien-Pin Chou, Hiromi Nakai

    The Journal of Physical Chemistry A   122 ( 1 ) 33 - 40  2018.01  [Refereed]

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    13
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  • Rigorous pKa Estimation of Amine Species Using Density-Functional Tight-Binding-Based Metadynamics Simulations

    Aditya Wibawa Sakti, Yoshifumi Nishimura, Hiromi Nakai

    Journal of Chemical Theory and Computation   14 ( 1 ) 351 - 356  2018.01  [Refereed]

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    35
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  • Release of DCDFTBMD Program

    Yoshifumi Nishimura, Takeshi Yoshikawa, Hiromi Nakai

    Journal of Computer Chemistry, Japan   17 ( 5 ) A21 - A27  2018  [Refereed]

  • Development of density-functional tight-binding repulsive potentials for bulk zirconia using particle swarm optimization algorithm

    Aulia S. Hutama, Yoshifumi Nishimura, Chien-Pin Chou, Stephan Irle

    AIP Conference Proceedings   1906 ( 1 ) 030015  2017.11  [Refereed]

     View Summary

    We report the preliminary results of the development of density-functional tight-binding (DFTB) repulsive potentials for the Zr - O element pair. The repulsive potentials were created using a computer code based on the particle swarm optimization. The potentials were tested on a set of systems for high temperature phases of bulk ZrO2, namely cubic and tetragonal. The potential sets were primarily developed for simulation of zirconia phase transitions at elevated temperatures.

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    3
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  • Errata: Divide-and-Conquer Density-Functional Tight-Binding Molecular Dynamics Study on the Formation of Carbamate Ions during CO2 Chemical Absorption in Aqueous Amine Solution

    Aditya Wibawa Sakti, Yoshifumi Nishimura, Hiroshi Sato, Hiromi Nakai

    Bulletin of the Chemical Society of Japan   91 ( 2 ) 318 - 318  2017.11  [Refereed]

    DOI

  • Divide-and-Conquer Density-Functional Tight-Binding Molecular Dynamics Study on the Formation of Carbamate Ions during CO2 Chemical Absorption in Aqueous Amine Solution

    Aditya Wibawa Sakti, Yoshifumi Nishimura, Hiroshi Sato, Hiromi Nakai

    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN   90 ( 11 ) 1230 - 1235  2017.11  [Refereed]

     View Summary

    Divide-and-conquer-type density-functional tight-binding molecular dynamics simulations of the CO2 absorption process in monoethanolamine (MEA) solution have been performed for systems containing thousands of atoms. The formation of carbamate anions has been widely investigated for neutral systems via ab initio molecular dynamics simulations, yet the present study is aimed at identifying the role of hydroxide ions in acid-base equilibrium. The structural and electronic analyses reveal that the hydroxide ion approaches, via Grotthuss-type shuttling, the zwitterionic intermediates and abstracts a proton from the nitrogen atom of MEA. We also estimated the fraction of reacted CO2 and carbamate formed at different initial CO2 concentrations that confirm a high absorbed CO2 concentration decreases the fraction of MEA(C) formed due to the abundance of MEA(Z) in the solution.

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  • Quantum Chemical Estimation of Acetone Physisorption on Graphene Using Combined Basis Set and Size Extrapolation Schemes

    Yoshifumi Nishimura, Takao Tsuneda, Takeshi Sato, Michio Katouda, Stephan Irle

    JOURNAL OF PHYSICAL CHEMISTRY C   121 ( 16 ) 8999 - 9010  2017.04  [Refereed]

     View Summary

    The physisorption of an acetone molecule oil hexagonal graphene nanoflakes with increasing size has been investigated using a variety of quantum chemical methods capable of describing weak intermolecular interactions coupled-cluster theory (CCSD and CCSD(T)), second-order Moller-Plesset perturbation theory with and without spin-component scaling (SCS-MP2 or standard MP2), long-range corrected density functional theory combined with a van der Waals functional (LC-BOP+ALL), meta-generalized gradient approximation functionals (M06-2X and M05-2X), and the dispersion augmented self-consistent-charge density functional tight-binding (SCC-DFTB-D) method. Our benchmark results for model systems as large as. dicircumcoronene C96H24 have confirmed the suitability of the SCS-MP2 method for this specific system and the satisfactory performance of the computationally much more economical semiempirical SCC-DFTB-D method. The latter delivers a qualitatively accurate description of physisorption for flakes Containing more than 800 carbon atoms. We predict accurate interaction energies of acetone with an infinitely large, defect-free graphene monolayer by combining extrapolation approaches for both increasing ab initio basis sets and graphene flake size in a two-dimensional extrapolation scheme:

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    5
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  • Divide-and-Conquer-Type Density-Functional Tight-Binding Simulations of Hydroxide Ion Diffusion in Bulk Water

    Aditya Wibawa Sakti, Yoshifumi Nishimura, Hiromi Nakai

    JOURNAL OF PHYSICAL CHEMISTRY B   121 ( 6 ) 1362 - 1371  2017.02  [Refereed]

     View Summary

    The diffusion of the hydroxide ion in bulk water was examined by linear-scaling divide-and-conquer density functional tight-binding molecular dynamics (DC-DFTB-MD) simulations using three different-sized unit cells that contained 522, 1050, and 4999 water molecules as well as one hydroxide ion. The repulsive potential for the oxygen-oxygen pair was improved by iterative Boltzmann inversion, which adjusted the radial distribution function of DFTB-MD simulations to that of the reference density functional theory-MD one. The calculated diffusion coefficients and the Arrhenius diffusion barrier were in good agreement with experimental results. The results of the hydroxide ion coordination number distribution and potential of mean force analyses supported a dynamical hypercoordination diffusion mechanism.

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    34
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  • Parallel implementation of efficient charge-charge interaction evaluation scheme in periodic divide-and-conquer density-functional tight-binding calculations

    Yoshifumi Nishimura, Hiromi Nakai

    JOURNAL OF COMPUTATIONAL CHEMISTRY   39 ( 2 ) 105 - 116  2017.01  [Refereed]

     View Summary

    A low-computational-cost algorithm and its parallel implementation for periodic divide-and-conquer density-functional tight-binding (DC-DFTB) calculations are presented. The developed algorithm enables rapid computation of the interaction between atomic partial charges, which is the bottleneck for applications to large systems, by means of multipole- and interpolation-based approaches for long- and short-range contributions. The numerical errors of energy and forces with respect to the conventional Ewald-based technique can be under the control of the multipole expansion order, level of unit cell replication, and interpolation grid size. The parallel performance of four different evaluation schemes combining previous approaches and the proposed one are assessed using test calculations of a cubic water box on the K computer. The largest benchmark system consisted of 3,295,500 atoms. DC-DFTB energy and forces for this system were obtained in only a few minutes when the proposed algorithm was activated and parallelized over 16,000 nodes in the K computer. The high performance using a single node workstation was also confirmed. In addition to liquid water systems, the feasibility of the present method was examined by testing solid systems such as diamond form of carbon, face-centered cubic form of copper, and rock salt form of sodium chloride. (c) 2017 Wiley Periodicals, Inc.

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    26
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  • Three pillars for achieving quantum mechanical molecular dynamics simulations of huge systems: Divide-and-conquer, density-functional tight-binding, and massively parallel computation

    Hiroaki Nishizawa, Yoshifumi Nishimura, Masato Kobayashi, Stephan Irle, Hiromi Nakai

    JOURNAL OF COMPUTATIONAL CHEMISTRY   37 ( 21 ) 1983 - 1992  2016.08  [Refereed]

     View Summary

    The linear-scaling divide-and-conquer (DC) quantum chemical methodology is applied to the density-functional tight-binding (DFTB) theory to develop a massively parallel program that achieves on-the-fly molecular reaction dynamics simulations of huge systems from scratch. The functions to perform large scale geometry optimization and molecular dynamics with DC-DFTB potential energy surface are implemented to the program called DC-DFTB-K. A novel interpolation-based algorithm is developed for parallelizing the determination of the Fermi level in the DC method. The performance of the DC-DFTB-K program is assessed using a laboratory computer and the K computer. Numerical tests show the high efficiency of the DC-DFTB-K program, a single-point energy gradient calculation of a one-million-atom system is completed within 60 s using 7290 nodes of the K computer. (c) 2016 Wiley Periodicals, Inc.

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  • Infrared absorption spectrum of the simplest deuterated Criegee intermediate CD2OO

    Yu-Hsuan Huang, Yoshifumi Nishimura, Henryk A. Witek, Yuan-Pern Lee

    JOURNAL OF CHEMICAL PHYSICS   145 ( 4 ) 044305  2016.07  [Refereed]

     View Summary

    We report a transient infrared (IR) absorption spectrum of the simplest deuterated Criegee intermediate CD2OO recorded using a step-scan Fourier-transform spectrometer coupled with a multipass absorption cell. CD2OO was produced from photolysis of flowing mixtures of CD2I2, N-2, and O-2 (13 or 87 Torr) with laser light at 308 nm. The recorded spectrum shows close structural similarity with the spectrum of CH2OO reported previously [Y.-T. Su et al., Science 340, 174 (2013)]. The four bands observed at 852, 1017, 1054, and 1318 cm(-1) are assigned to the OO stretching mode, two distinct in-plane OCD bending modes, and the CO stretching mode of CD2OO, respectively, according to vibrational wavenumbers, IR intensities, rotational contours, and deuterium-isotopic shifts predicted with extensive quantum-chemical calculations. The CO-stretching mode of CD2OO at 1318 cm(-1) is blue shifted from the corresponding band of CH2OO at 1286 cm(-1); this can be explained by a mechanism based on mode mixing and isotope substitution. A band near 936 cm(-1), observed only at higher pressure (87 Torr), is tentatively assigned to the CD2 wagging mode of CD2IOO. Published by AIP Publishing.

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  • Contrasting mechanisms for CO2 absorption and regeneration processes in aqueous amine solutions: Insights from density-functional tight-binding molecular dynamics simulations

    Hiromi Nakai, Yoshifumi Nishimura, Takeaki Kaiho, Takahito Kubota, Hiroshi Sato

    CHEMICAL PHYSICS LETTERS   647   127 - 131  2016.03  [Refereed]

     View Summary

    CO2 chemical absorption and regeneration processes in aqueous amine solutions were investigated using density-functional tight-binding molecular dynamics simulations. Extensive analyses of the structural, electronic, and dynamical properties of 100 independent trajectories supported the contrasting mechanisms in the absorption and regeneration processes. In the CO2 absorption process, bicarbonate formed where the hydroxyl anion migrated through the hydrogen-bond network of water molecules, namely, by a Grotthuss-type mechanism. On the other hand, direct proton transfer from the protonated amine to the hydroxyl group of bicarbonate, which is called the ion-pair mechanism, was the key step to the release of CO2. (C) 2016 Elsevier B.V. All rights reserved.

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  • Divide-and-Conquer-Type Density-Functional Tight-Binding Molecular Dynamics Simulations of Proton Diffusion in a Bulk Water System

    Hiromi Nakai, Aditya Wibawa Sakti, Yoshifumi Nishimura

    JOURNAL OF PHYSICAL CHEMISTRY B   120 ( 1 ) 217 - 221  2016.01  [Refereed]

     View Summary

    The process of proton diffusion in liquid water was investigated using molecular dynamics (MD) simulations, and the total energy and atomic forces were evaluated by the divide-and-conquer-type density-functional tight-binding (DC-DFTB) method. The effectiveness of this approach was confirmed by comparing the computational time of water clusters with conventional treatments. The unit cell employed herein, which contained 523 water molecules and 1 excess proton, was moderately large in comparison with those used in previous studies. The reasonable accuracy obtained by using this unit cell was confirmed by examining the temperature fluctuation. The diffusion coefficients for the vehicular and Grotthuss processes were accurately reproduced by the DC-DFTB-MD simulations with the unit cell containing 523 water molecules. Furthermore, the energy barriers were evaluated from the temperature dependence of the diffusion coefficient for each process. The calculated barrier for Grotthuss diffusion was in good agreement with the experimental value.

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  • Automatized Parameterization of DFTB Using Particle Swarm Optimization

    Chien-Pin Chou, Yoshifumi Nishimura, Chin-Chai Fan, Grzegorz Mazur, Stephan Irle, Henryk A. Witek

    JOURNAL OF CHEMICAL THEORY AND COMPUTATION   12 ( 1 ) 53 - 64  2016.01  [Refereed]

     View Summary

    We present a novel density-functional tight-binding (DFTB) parametrization toolkit developed to optimize the parameters of various DFTB models in a fully automatized fashion. The main features of the algorithm, based on the particle swarm optimization technique, are discussed, and a number of initial pilot applications of the developed methodology to molecular and solid systems are presented.

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  • Automatized Parameterization of the Density-functional Tight-binding Method. II. Two-center Integrals

    Henryk A. Witek, Chien-Pin Chou, Grzegorz Mazur, Yoshifumi Nishimura, Stephan Irle, Balint Aradi, Thomas Frauenheim, Keiji Morokuma

    JOURNAL OF THE CHINESE CHEMICAL SOCIETY   63 ( 1 ) 57 - 68  2016.01  [Refereed]

     View Summary

    We present an efficient numerical integration scheme (TWOCENT) to be used in the context of automatized parameterization of the density-functional tight-binding (DFTB) method. The accuracy of the integration process is assessed and its range of applicability is discussed. The functionality of the developed code is tested by reproducing the electronic portion of the existing mio parameter sets and by reproducing a series of reference DFT band structures of elemental solids.

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    16
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  • Infrared identification of the Criegee intermediates syn- and anti-CH3CHOO, and their distinct conformation-dependent reactivity

    Hui-Yu Lin, Yu-Hsuan Huang, Xiaohong Wang, Joel M. Bowman, Yoshifumi Nishimura, Henryk A. Witek, Yuan-Pern Lee

    NATURE COMMUNICATIONS   6   7012  2015.05  [Refereed]

     View Summary

    The Criegee intermediates are carbonyl oxides that play critical roles in ozonolysis of alkenes in the atmosphere. So far, the mid-infrared spectrum of only the simplest Criegee intermediate CH2OO has been reported. Methyl substitution of CH2OO produces two conformers of CH3CHOO and consequently complicates the infrared spectrum. Here we report the transient infrared spectrum of syn- and anti-CH3CHOO, produced from CH3CHI + O-2 in a flow reactor, using a step-scan Fourier-transform spectrometer. Guided and supported by high-level full-dimensional quantum calculations, rotational contours of the four observed bands are simulated successfully and provide definitive identification of both conformers. Furthermore, anti-CH3CHOO shows a reactivity greater than syn-CH3CHOO towards NO/NO2; at the later period of reaction, the spectrum can be simulated with only syn-CH3CHOO. Without NO/NO2, anti-CH3CHOO also decays much faster than syn-CH3CHOO. The direct infrared detection of syn-and anti-CH3CHOO should prove useful for field measurements and laboratory investigations of the Criegee mechanism.

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  • Mechanism of Back Electron Transfer in an Intermolecular Photoinduced Electron Transfer Reaction: Solvent as a Charge Mediator

    Sudhakar Narra, Yoshifumi Nishimura, Henryk A. Witek, Shinsuke Shigeto

    CHEMPHYSCHEM   15 ( 14 ) 2945 - 2950  2014.10  [Refereed]

     View Summary

    Back electron transfer (BET) is one of the important processes that govern the decay of generated ion pairs in intermolecular photoinduced electron transfer reactions. Unfortunately, a detailed mechanism of BET reactions remains largely unknown in spite of their importance for the development of molecular photovoltaic structures. Here, we examine the BET reaction of pyrene (Py) and 1,4-dicyanobenzene (DCB) in acetonitrile (ACN) by using time-resolved near-and mid-IR spectroscopy. The Py dimer radical cation (Py-2(center dot+)) and DCB radical anion (DCB center dot-) generated after photoexcitation of Py show asynchronous decay kinetics. To account for this observation, we propose a reaction mechanism that involves electron transfer from DCB center dot- to the solvent and charge recombination between the resulting ACN dimer anion and Py-2(center dot+). The unique role of ACN as a charge mediator revealed herein could have implications for strategies that retard charge recombination in dye-sensitized solar cells.

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  • Critical interpretation of CH- and OH- stretching regions for infrared spectra of methanol clusters (CH3OH)(n) (n=2-5) using self-consistent-charge density functional tight-binding molecular dynamics simulations

    Yoshifumi Nishimura, Yuan-Pern Lee, Stephan Irle, Henryk A. Witek

    JOURNAL OF CHEMICAL PHYSICS   141 ( 9 ) 094303  2014.09  [Refereed]

     View Summary

    Vibrational infrared (IR) spectra of gas-phase O-H center dot center dot center dot O methanol clusters up to pentamer are simulated using self-consistent-charge density functional tight-binding method using two distinct methodologies: standard normal mode analysis and Fourier transform of the dipole time-correlation function. The twofold simulations aim at the direct critical assignment of the C-H stretching region of the recently recorded experimental spectra [H.-L. Han, C. Camacho, H. A. Witek, and Y.-P. Lee, J. Chem. Phys. 134, 144309 (2011)]. Both approaches confirm the previous assignment (ibid.) of the C-H stretching bands based on the B3LYP/ANO1 harmonic frequencies, showing that nu(3), nu(9), and nu(2) C-H stretching modes of the proton-accepting (PA) and proton-donating (PD) methanol monomers experience only small splittings upon the cluster formation. This finding is in sharp discord with the assignment based on anharmonic B3LYP/VPT2/ANO1 vibrational frequencies (ibid.), suggesting that some procedural faults, likely related to the breakdown of the perturbational vibrational treatment, led the anharmonic calculations astray. The IR spectra based on the Fourier transform of the dipole time-correlation function include new, previously unaccounted for physical factors such as non-zero temperature of the system and large amplitude motions of the clusters. The elevation of temperature results in a considerable non-homogeneous broadening of the observed IR signals, while the presence of large-amplitude motions (methyl group rotations and PA-PD flipping), somewhat surprisingly, does not introduce any new features in the spectrum. (C) 2014 AIP Publishing LLC.

    DOI

    Scopus

    18
    Citation
    (Scopus)
  • Theoretical study of cellobiose hydrolysis to glucose in ionic liquids

    Yoshifumi Nishimura, Daisuke Yokogawa, Stephan Irle

    CHEMICAL PHYSICS LETTERS   603   7 - 12  2014.05  [Refereed]

     View Summary

    The S(N)1-type hydrolysis reaction of cellobiose in ionic liquids (ILs) was theoretically investigated. First principles and ab initio quantum chemical methods were used in conjunction with the 'reference interaction site model self-consistent field with spatial electron density distribution' (RISM-SCF-SEDD) method. Reaction mechanism pathways are discussed and compared to calculations in gas phase and in aqueous solution. Analysis of solvation effects indicates strong interaction between hydrogen atoms of glucose hydroxyl groups and the anions in ILs, contributing to large stabilization of the reaction product. The calculated activation energy in ILs (24.5 kcal/mol) agrees quantitatively with the experimental value (26.5 kcal/mol). (C) 2014 Elsevier B. V. All rights reserved.

    DOI

    Scopus

    2
    Citation
    (Scopus)
  • Growth of carbon nanotubes via twisted graphene nanoribbons

    Hong En Lim, Yasumitsu Miyata, Ryo Kitaura, Yoshifumi Nishimura, Yoshio Nishimoto, Stephan Irle, Jamie H. Warner, Hiromichi Kataura, Hisanori Shinohara

    NATURE COMMUNICATIONS   4   2548  2013.10  [Refereed]

     View Summary

    Carbon nanotubes have long been described as rolled-up graphene sheets. It is only fairly recently observed that longitudinal cleavage of carbon nanotubes, using chemical, catalytical and electrical approaches, unzips them into thin graphene strips of various widths, the so-called graphene nanoribbons. In contrast, rolling up these flimsy ribbons into tubes in a real experiment has not been possible. Theoretical studies conducted by Kit et al. recently demonstrated the tube formation through twisting of graphene nanoribbon, an idea very different from the rolling-up postulation. Here we report the first experimental evidence of a thermally induced self-intertwining of graphene nanoribbons for the preferential synthesis of (7, 2) and (8, 1) tubes within parent-tube templates. Through the tailoring of ribbon's width and edge, the present finding adds a radically new aspect to the understanding of carbon nanotube formation, shedding much light on not only the future chirality tuning, but also contemporary nanomaterials engineering.

    DOI

    Scopus

    87
    Citation
    (Scopus)
  • Stochastic search of molecular cluster interaction energy surfaces with coupled cluster quality prediction. The phenylacetylene dimer

    Matthew A. Addicoat, Yoshifumi Nishimura, Takeshi Sato, Takao Tsuneda, Stephan Irle

    Journal of Chemical Theory and Computation   9 ( 8 ) 3848 - 3854  2013.08  [Refereed]

     View Summary

    We report a stochastic search methodology on the basis of dispersion-augmented density functional theory (DFT), aimed at finding low energy isomers of the phenylacetylene dimer as well as methane and benzene dimers. Stochastic search of the molecular cluster interaction energy surfaces was carried out with the computationally inexpensive dispersion-augmented, third-order self-consistent charge density functional tight-binding (DFTB3-D) method, and energetically low-lying molecular cluster geometries were identified, including several that had previously been optimized at the MP2/cc-pVTZ level of theory and had single point interaction energies evaluated at the coupled-cluster singles, doubles, and perturbative triples (CCSD(T)) level of theory in the complete basis set limit (Maity, S. et al. Phys. Chem. Chem. Phys 2011, 13, 16706). In addition, the search procedure identifies several additional low-energy isomers that map a reaction path, rotating one monomer through a full 360 relative to the first. We found that binding energies from long-range corrected functional combined with the local response dispersion correction (LC-BOP+LRD) yields binding energies that are within 1 kJ mol-1 of the CCSD(T)/CBS results for both π-stacked and CH···π structures. In contrast, other functionals and second-order Møller-Plesset perturbation methods favored one binding motif or the other and therefore are not ideal to describe a global potential energy surface. © 2013 American Chemical Society.

    DOI

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    2
    Citation
    (Scopus)
  • Dimerization-Initiated Preferential Formation of Coronene-Based Graphene Nanoribbons in Carbon Nanotubes

    Miho Fujihara, Yasumitsu Miyata, Ryo Kitaura, Yoshifumi Nishimura, Cristopher Camacho, Stephan Irle, Yoko Iizumi, Toshiya Okazaki, Hisanori Shinohara

    JOURNAL OF PHYSICAL CHEMISTRY C   116 ( 28 ) 15141 - 15145  2012.07  [Refereed]

     View Summary

    We have investigated the growth mechanism of coronene-derived graphene nanoribbons (GNRs) using two different precursors: coronene and a dimer form of coronene, so-called dicoronylene (C48H20). For both of the precursors, the formation of nanoribbon-like materials inside carbon nanotubes (CNTs) was confirmed by transmission electron microscope observations. Experimental and theoretical Raman analysis reveals that the samples also encapsulated dicoronylene and linearly condensed other coronene oligomers, which can be regarded as analogues to GNRs. Interestingly, it was found that the present doping condition of coronene yields dicoronylene prior to encapsulation due to the thermal dimerization of coronene. These results indicate that the dimerization before the encapsulation drives the preferential formation of the coronene-based GNRs within CNTs.

    DOI

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    83
    Citation
    (Scopus)
  • Relative Isomer Abundance of Fullerenes and Carbon Nanotubes Correlates with Kinetic Stability (vol 107, 175506, 2011)

    A. S. Fedorov, D. A. Fedorov, A. A. Kuzubov, P. V. Avramov, Y. Nishimura, S. Irle, Henryk A. Witek

    PHYSICAL REVIEW LETTERS   108 ( 24 ) 249902  2012.06  [Refereed]

    DOI

    Scopus

    1
    Citation
    (Scopus)
  • Relative Isomer Abundance of Fullerenes and Carbon Nanotubes Correlates with Kinetic Stability

    A. S. Fedorov, D. A. Fedorov, A. A. Kuzubov, P. V. Avramov, Y. Nishimura, S. Irle, Henryk A. Witek

    PHYSICAL REVIEW LETTERS   107 ( 17 ) 175506  2011.10  [Refereed]

     View Summary

    A methodology to evaluate the kinetic stability of carbon nanostructures is presented based on the assumption of the independent and random nature of thermal vibrations. The kinetic stability is directly correlated to the cleavage probability for the weakest bond of a given nanostructure. The application of the presented method to fullerenes and carbon nanotubes yields clear correlation to their experimentally observed relative isomer abundances. The general and simple formulation of the method ensures its applicability to other nanostructures for which formation is controlled by kinetic factors.

    DOI

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    22
    Citation
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  • Dramatic Reduction of IR Vibrational Cross Sections of Molecules Encapsulated in Carbon Nanotubes

    Dmitry V. Kazachkin, Yoshifumi Nishimura, Henryk A. Witek, Stephan Irle, Eric Borguet

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   133 ( 21 ) 8191 - 8198  2011.06  [Refereed]

     View Summary

    Combined temperature-programmed desorption and IR studies suggest that absorption cross sections of IR-active vibrations of molecules "strongly" bound to single-wall sidewalls as the origin of such "screening". The observed and identify dielectric screening by highly polarizable SWCNT endohedrally encapsulated molecules are dramatically reduced, carbon nanotubes (SWCNTs) are reduced at least by a factor of 10. Quantum chemical simulations show that IR intensities of intensity reduction originates from a sizable cancellation of adsorbate dipole moments by mirror charges dynamically induced on the nanotube sidewalls. For exohedrally adsorbed molecules, the dielectric screening is found to be orientation-dependent with a smaller magnitude for adsorption in groove and interstitial sites. The presented results clearly demonstrate and quantify the screening effect of SWCNTs and unequivocally show that IR spectroscopy cannot be applied in a straightforward manner to the study of peapod systems.

    DOI

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    34
    Citation
    (Scopus)
  • Temperature and pressure dependence of molecular adsorption on single wall carbon nanotubes and the existence of an "adsorption/desorption pressure gap"

    Dmitry V. Kazachkin, Yoshifumi Nishimura, Stephan Irle, Xue Feng, Radisav Vidic, Eric Borguet

    CARBON   48 ( 7 ) 1867 - 1875  2010.06  [Refereed]

     View Summary

    The interaction of acetone with single wall carbon nanotubes (SWCNTs) was studied by temperature programmed desorption with mass spectrometry (TPD-MS), after reflux, sonication, or exposure to 7.6 Torr of acetone vapors at room temperature. Acetone molecules adsorb strongly on SWCNTs desorbing at similar to 400-900 K, corresponding to desorption energies of similar to 100-225 kJ/mol, as intact molecules. Exchange of intact adsorbed molecules with gas phase species was observed in successive dosing of hydrogenated and deuterated acetone molecules. The desorption energies reported here are in stark contrast to the desorption energies (similar to 75 kJ/mol) reported earlier for SWCNTs interacting with acetone under high vacuum at cryogenic temperatures. This result suggests activated adsorption/desorption, and is also observed for adsorption of ethanol, methane, n-butane and 1,3-butadiene on SWCNTs and on carbon black. Quantum chemical calculations suggest that adsorption in interstitial channels of bundles formed of large-diameter SWCNTs is possible and can account for high desorption barriers, a result of strong dispersion interactions between neighboring SWCNTs. (C) 2009 Elsevier Ltd. All rights reserved.

    DOI

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    20
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  • Interaction of acetone with single wall carbon nanotubes at cryogenic temperatures: A combined temperature programmed desorption and theoretical study

    Dmitry Kazachkin, Yoshifumi Nishimura, Stephan Irle, Keiji Morokuma, Radisav D. Vidic, Eric Borguet

    LANGMUIR   24 ( 15 ) 7848 - 7856  2008.08  [Refereed]

     View Summary

    The interaction of acetone with single wall carbon nanotubes (SWCNTs) at low temperatures was studied by a combination of temperature programmed desorption (TPD) and dispersion-augmented density-functional-based tight binding (DFTB-D) theoretical simulations. On the basis of the results of the TPD study and theoretical simulations, the desorption peaks of acetone can be assigned to the following adsorption sites: (i) sites with energy of similar to 75 kJ mol(-1) (T-des similar to 300 K)-endohedral sites of small diameter nanotubes (similar to 7.7 angstrom); (ii) sites with energy 40-68 kJ mol(-1) (T-des similar to 240 K)-acetone adsorption on accessible interstitial, groove sites, and endohedral sites of larger nanotubes (similar to 14 angstrom); (iii) sites with energy 25-42 kJ mol(-1) (T-des similar to 140 K)-acetone adsorption on external walls of SWCNTs and multilayer adsorption. Oxidatively purified SWCNTs have limited access to endohedral sites due to the presence of oxygen functionalities. Oxygen functionalities can be removed by annealing to elevated temperature (900 K) opening access to endohedral sites of nanotubes. Nonpurified, as-received SWCNTs are characterized by limited access for acetone to endohedral sites even after annealing to elevated temperatures (900 K). Annealing of both purified and as-produced SWCNTs to high temperatures (1400 K) leads to reduction of access for acetone molecules to endohedral sites of small nanotubes, probably due to defect self-healing and cap formation at the ends of SWCNTs. No chemical interaction between acetone and SWCNTs was detected for low temperature adsorption experiments. Theoretical simulations of acetone adsorption on finite pristine SWCNTs of different diameters suggest a clear relationship of the adsorption energy with tube sidewall curvature. Adsorption of acetone is due to dispersion forces, with its C-O bond either parallel to the surface or 0 pointing away from it. No significant charge transfer or polarization was found. Carbon black was used to model amorphous carbonaceous impurities present in as-produced SWCNTs. Desorption of acetone from carbon black revealed two peaks at similar to 140 and similar to 180-230 K, similar to two acetone desorption peaks from SWCNTs. The characteristic feature of acetone desorption from SWCNTs was peak at similar to 300 K that was not observed for carbon black. Care should be taken when assigning TPD peaks for molecules desorbing front carbon nanotubes as amorphous carbon can interfere.

    DOI

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    31
    Citation
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Presentations

  • Recent updates of DCDFTBMD program: Theory, implementation, and applications

    Hiromi Nakai, Yoshifumi Nishimura  [Invited]

    Asia Pacific Conference of Theoretical and Computational Chemistry (APATCC-10) 

    Presentation date: 2023.02

  • 量子的分子動力学計算プログラムDCDFTBMDの開発状況と最近の応用事例

    西村 好史  [Invited]

    スーパーコンピュータワークショップ2022「 複雑電子状態の理論・計算科学」 

    Presentation date: 2023.01

  • Recently added features in DCDFTBMD program

    Yoshifumi Nishimura, Hiromi Nakai  [Invited]

    New Horizons in Scientific Software: THE NEW COLLABORATIVE PLATFORM GOES LIFE (NHISS2022) 

    Presentation date: 2022.12

  • Recent developments in divide-and-conquer density functional tight-binding method

    Yoshifumi Nishimura, Takeshi Yoshikawa, Hiromi Nakai  [Invited]

    The 2021 International Chemical Congress of Pacific Basin Societies 

    Presentation date: 2021.12

  • DCDFTBMD: Divide-and-conquer density functional tight-binding program for huge-system quantum mechanical molecular dynamics simulations

    Hiromi Nakai, Yoshifumi Nishimura  [Invited]

    New Horizons in Scientific Software: from Legacy Codes to Modular Environments (NHISS2020) 

    Presentation date: 2020.11

  • Development of Large-scale Quantum Mechanical Molecular Dynamics Simulation: Divide-and-Conquer Density Functional Tight-binding Approach

    Yoshifumi Nishimura, Aditya Wibawa Sakti, Hiromi Nakai  [Invited]

    First International Workshop on Advanced Methods for Nano Materials Design – Satellite session of Nano Korea 2017 Symposium 

    Presentation date: 2017.07

  • 分割統治型密度汎関数強束縛分子動力学(DC-DFTB-MD)シミュレーションの開発・応用と展望

    西村 好史  [Invited]

    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1回連携推進ワークショップ :触媒元素戦略研究との連携を求めて 

    Presentation date: 2016.11

  • Development of linear-scaling divide-and-conquer density-functional tight-binding program: massively parallel DC-DFTB calculations on the K computer

    Yoshifumi Nishimura  [Invited]

    5th International Workshop on Massively Parallel Programming Now in Quantum Chemistry and Physics – Toward Exascale Computing 

    Presentation date: 2015.11

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Research Projects

  • CO2 reduction drive at low pressure using CO2 pseudo high-pressure field

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Transformative Research Areas (B)

    Project Year :

    2022.05
    -
    2025.03
     

  • Development and application of hierarchical simulation system based on large-scale quantum chemical calculations

    Japan Society for the Promotion of Science  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)

    Project Year :

    2022.04
    -
    2025.03
     

  • 大規模量子分子動力学計算技術の社会実装に関する研究

    早稲田大学  奨励研究

    Project Year :

    2021.10
    -
    2024.09
     

    西村 好史

  • 大規模励起状態ダイナミクスの開発及び光活性イエロータンパク質への実践的応用

    日本学術振興会  科学研究費助成事業 基盤研究(C)

    Project Year :

    2020.04
    -
    2023.03
     

    吉川 武司, 西村 好史

     View Summary

    代表的な光受容タンパク質であるPYPの光異性化過程に着目し、その光励起により誘起されるプロトン移動ダイナミクスの全容解明を目指す。そのために、スーパーコンピュータ「京」で卓越した成果を挙げている分割統治密度汎関数強束縛分子動力学(DC-DFTB-MD)法を励起状態へと拡張し、大規模励起状態ダイナミクス法の基盤を確立しその応用計算を行う。昨年度までに、理論研究では、DC-DFTB-MD法を励起状態へと拡張するため、新たに分割統治時間依存密度汎関数強束縛分子動力学(DC-TDDFTB-MD)法の開発・実装を行った。
    励起状態の検証のため、光活性イエロータンパク質の光異性化は無輻射失活過程であるため、円錐交差(CI)構造を高速かつ精度よく再現できる手法が必要となった。DC-DFTB-MDプログラムに対してコストと精度のバランスのよいスピン反転(SF)法を導入した。SF法をDFTB法に導入することにより、非常に高速にCI構造を再現することができた。また、CI構造の電子状態を解析するために凍結起動近似を用いたエネルギー成分の分解(クーロン項・交換項等)を行い、CI構造へと推移するための支配因子の解明も行った。その支配因子を用いることにより、より容易にCI構造探索が可能となった。
    光活性イエロータンパク質の活性中心はp-クマル酸の反応サイクルにおけるプロトン移動に関する検証を行った。また、変異体におけるプロトン移動に関しても検討を行い、活性中心の周辺残基による効果がプロトン移動の障壁に対して寄与を持つことが示唆された。

Misc

  • Quantum Molecular Dynamics Simulation for trans-cis Photoisomerization Process in Photocycle of Photoactive Yellow Protein

    Kensuke ISHIDA, Yoshifumi NISHIMURA, Hiromi NAKAI

    Journal of Computer Chemistry, Japan   22 ( 2 ) 9 - 11  2023.11

    DOI

  • バクテリオロドプシンの分子動画に基づく大規模量子分子動力学法によるプロトン移動反応の解析

    小野 純一, 今井 みの莉, 西村 好史, 中井 浩巳

    分子シミュレーション学会誌アンサンブル   23 ( 3 ) 171 - 175  2021.07

    Article, review, commentary, editorial, etc. (scientific journal)  

    DOI

  • DCDFTBMDプログラムの公開

    西村 好史, 吉川 武司, 中井 浩巳

    Journal of Computer Chemistry, Japan   17 ( 5 ) A21 - A27  2019.03

    Article, review, commentary, editorial, etc. (scientific journal)  

    DOI

  • 分割統治型密度汎関数強束縛 (DC-DFTB)法に対する最近の開発と応用

    西村 好史, 中井 浩巳

    分子シミュレーション研究会会誌アンサンブル   20 ( 1 ) 18 - 23  2018.01

    Article, review, commentary, editorial, etc. (scientific journal)  

    DOI

  • 分割統治型密度汎関数強束縛分子動力学(DC-DFTB-MD)法によるナノスケール系化学反応シミュレーション

    西村 好史, 中井 浩巳

    分子シミュレーション研究会会誌アンサンブル   18 ( 2 ) 95 - 101  2016.04

    Article, review, commentary, editorial, etc. (scientific journal)  

     View Summary

    <p>量子化学的手法を用いた分子動力学(QM/MD)シミュレーションは,化学反応の動的過程を微視的に理解するための有効な解析手法の一つである.しかし,数千〜数万個の原子を含む実在系に即したモデルを取り扱うためには,QM/MD計算コストの抜本的な削減が不可欠である.本稿では,密度汎関数強束縛法と分割統治法の組み合わせにより低プレファクタと線形スケーリングを同時に満たす手法とその計算プログラムの並列性能評価,およびナノスケール系への応用例を紹介する.</p>

    DOI CiNii

  • Recent Advances in Divide-and- Conquer Density-Functional Tight-Binding Molecular Dynamics Simulations (DC-DFTB-MD)

    Yoshifumi Nishimura, Takeaki Kaiho, Hiromi Nakai

    Journal of Computer Chemistry, Japan   14 ( 3 ) 43 - 46  2015.09

    Article, review, commentary, editorial, etc. (scientific journal)  

    DOI

  • Two mutually exclusive DFTB parameter sets for the simulation of chemical hydrogen sputtering on beryllium walls

    Yoshifumi Nishimura, Jun Saito, Daisuke Yokogawa, Chien-Pin Chou, Henryk A. Witek, Stephan Irle

    Journal of Plasma and Fusion Research   89 ( 9 ) 594 - 598  2013.09

    Article, review, commentary, editorial, etc. (scientific journal)  

  • First Principles-Based Estimate of the Critical SWCNT Length for Raman D and G Band Intensity Inversion

    Yoshifumi Nishimura, Henryk Witek, Stephan Irle

    ECS Meeting Abstracts   MA2013-01 ( 32 ) 1132 - 1132  2013.03

     View Summary

    Abstract not Available.

    DOI

  • (Invited) Dramatic Reduction of IR Vibrational Cross-sections of Molecules Encapsulated in Carbon Nanotubes

    Dmitry Kazachkin, Yoshifumi Nishimura, Henryk Witek, Stephan Irle, Eric Borguet

    ECS Meeting Abstracts   MA2012-01 ( 32 ) 1188 - 1188  2012.02

     View Summary

    Abstract not Available.

    DOI

  • COLL 170-Interaction of simple molecules with carbon nanotubes

    Dmitry V. Kazachkin, Yoshifumi Nishimura, Nikolay Dementev, Stephan Irle, Keiji Morokuma, Radisav Vidic, Eric Borguet

    ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY   236  2008.08

    Research paper, summary (international conference)  

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Teaching Experience

  • 化学数学1

    東京理科大学