Updated on 2024/03/28

写真a

 
SAITOW Masaaki
 
Organization
Research Center for Materials Science Assistant Professor
Graduate School
Graduate School of Science
Title
Assistant Professor

Degree 1

  1. Doctor of Philosophy ( 2014.4   The Graduate University for Advanced Studies ) 

Research Interests 4

  1. Open-shell molecules

  2. Electron correlation

  3. Quantum Chemistry

  4. Electronic structure

Research Areas 1

  1. Nanotechnology/Materials / Fundamental physical chemistry  / Theoretical Chemistry

Current Research Project and SDGs 1

  1. Efficient and accurate electronic structure theory for large, real-life molecules

 

Papers 27

  1. Quasi-degenerate extension of local N-electron valence state perturbation theory with pair-natural orbital method based on localized virtual molecular orbitals

    Manami Hayashi, Masaaki Saitow, Kazuma Uemura, Takeshi Yanai

    Chemarxiv     2024.2

     More details

    Authorship:Corresponding author   Language:English  

    Chemical phenomena involving near-degenerate electronic states, such as conical intersections or avoided crossing, can be properly described using quasi-degenerate perturbation theory (QDPT). This study proposed a highly scalable quasi-degenerate second-order N-electron valence state perturbation theory (QD-NEVPT2) using the local pair-natural orbital (PNO) method. Our recent study showed an efficient implementation of the PNO-based state-specific (SS) NEVPT2 method using orthonormal localized virtual molecular orbitals (LVMOs) as an intermediate local basis. This study derived the state-coupling (or off-diagonal) terms to imple- ment QD-NEVPT2 in an alternative manner to enhance efficiency based on the internally contracted basis (ICB) and PNO overlap matrices between different references. To facilitate further acceleration, a local resolution-of-the-identity (RI) three-index integral generation algorithm was developed using LMOs and LVMOs. Although the NEVPT2 theory is considered to be less susceptible to the intruder-state problem (ISP), this study revealed that it can easily suffer from ISP when calculating high-lying excited states. We ameliorated this instability using the imaginary level shift (LS) technique. The PNO-QD-NEVPT2 calculations were performed on small organic molecules for the 30 lowest-lying states, as well as photoisomerization involving the conical intersection of 1,1- dimethyldibenzo[b,f] silepin with a cis-stilbene skeleton. These calculations revealed that the PNO-QD-NEVPT2 method yielded negligible errors compared to the canonical QD-NEVPT2 results. Furthermore, we tested its applicability to a large photoisomeriza- tion system using the green fluorescent protein model and the 10-state calculation of the large transition metal complex, showcasing that off-diagonal elements can be evaluated at a relatively low cost.

  2. Local N-electron valence state perturbation theory using pair-natural orbitals based on localized virtual molecular orbitals Invited Reviewed

    Kazuma Uemura, Masaaki Saitow, Takaki Ishimaru, Takeshi Yanai

    Chemarxiv     2023.1

     More details

    Authorship:Corresponding author  

  3. A local pair-natural orbital-based complete-active space perturbation theory using orthogonal localized virtual molecular orbitals Reviewed

    Masaaki Saitow, Kazuma Uemura, Takeshi Yanai

    The Journal of Chemical Physics   Vol. 157 ( 8 ) page: 084101   2022.8

     More details

    Authorship:Lead author, Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

  4. Thermally Stable Array of Discrete C60s on a Two-Dimensional Crystalline Adlayer of Macrocycles both in Vacuo and under Ambient Pressure Reviewed

    Shin-ichiro Kawano, Masato Nakaya, Masaaki Saitow, Atsuki Ishiguro, Takeshi Yanai, Jun Onoe, and Kentaro Tanaka

    Journal of American Chemical Society     2022.3

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: https://doi.org/10.1021/jacs.1c13610

  5. Multireference Perturbation Theory Combined with PCM and RISM Solvation Models: A Benchmark Study for Chemical Energetics Reviewed

    Masaaki Saitow, Keisuke Hori, Ayaka Yoshikawa, Ryosuke Y. Shimizu, Daisuke Yokogawa, Takeshi Yanai

    Journal of Physical Chemistry A   Vol. 125 ( 37 ) page: 8324 - 8336   2021.9

     More details

    Authorship:Lead author, Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

    DOI: https://doi.org/10.1021/acs.jpca.1c05944

  6. 57Fe Mössbauer parameters from domain based local pair-natural orbital coupled-cluster theory Reviewed International coauthorship

    Dipayan Datta, Masaaki Saitow, Barbara Sandhöfer, Frank Neese

    The Journal of Chemical Physics   Vol. 153 ( 20 ) page: 204101   2020.11

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  7. A multireference coupled-electron pair approximation combined with complete-active space perturbation theory in local pair-natural orbital framework Reviewed

    Masaaki Saitow, Takeshi Yanai

    The Journal of chemical physics   Vol. 152 ( 11 ) page: 114111   2020.3

     More details

    Authorship:Lead author, Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

  8. Linear scaling perturbative triples correction approximations for open-shell domain-based local pair natural orbital coupled cluster singles and doubles theory [DLPNO-CCSD (T0/T)] Reviewed International coauthorship

    Yang Guo, Christoph Riplinger, Dimitrios G Liakos, Ute Becker, Masaaki Saitow, Frank Neese

    The Journal of chemical physics     2020.1

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  9. Accurate Ionization Potentials, Electron Affinities and Electronegativities of Single-Walled Carbon Nanotubes by State-of-the-Art Local Coupled-Cluster Theory Reviewed International coauthorship

    Masaaki Saitow, Achintya K Dutta, Frank Neese

    Bulletin of the Chemical Society of Japan   Vol. 92 ( 1 ) page: 170 - 174   2019.11

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  10. A domain-based local pair natural orbital implementation of the equation of motion coupled cluster method for electron attached states Reviewed International coauthorship

    Achintya Kumar Dutta, Masaaki Saitow, Baptiste Demoulin, Frank Neese, Róbert Izsák

    The Journal of chemical physics   Vol. 150 ( 16 ) page: 164123   2019.4

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  11. Local Energy Decomposition of Open-Shell Molecular Systems in the Domain-Based Local Pair Natural Orbital Coupled Cluster Framework Reviewed International coauthorship

    Ahmet Altun, Masaaki Saitow, Frank Neese, Giovanni Bistoni

    Journal of chemical theory and computation   Vol. 15 ( 3 ) page: 1616 - 1632   2019.1

     More details

    Language:English  

  12. Perturbative triples correction to domain-based local pair natural orbital variants of Mukherjee's state specific coupled cluster method Reviewed International coauthorship

    Jakub Lang, Jiří Brabec, Masaaki Saitow, Jiří Pittner, Frank Neese, Ondřej Demel

    Physical Chemistry Chemical Physics   Vol. 21 ( 9 ) page: 5022 - 5038   2019

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  13. Accurate spin-densities based on the domain-based local pair-natural orbital coupled-cluster theory Reviewed International coauthorship

    Masaaki Saitow, Frank Neese

    The Journal of chemical physics   Vol. 149 ( 3 ) page: 034104   2018.7

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  14. A near-linear scaling equation of motion coupled cluster method for ionized states Reviewed International coauthorship

    Achintya Kumar Dutta, Masaaki Saitow, Christoph Riplinger, Frank Neese, Róbert Izsák

    The Journal of chemical physics   Vol. 148 ( 24 ) page: 244101   2018.6

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  15. Domain-based Local Pair Natural Orbital version of Mukherjee's state specific coupled cluster method Reviewed

    J. Brabec, J. Lang, M. Saitow, J. Pittner, F. Neese, and O. Demel

    J. Chem. Theory Comput. Article   Vol. 14   page: 1370   2018

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  16. A new near-linear scaling, effi- cient and accurate, open-shell domain-based local pair natural orbital coupled cluster singles and doubles theory Reviewed International coauthorship

    M. Saitow, U. Becker, C. Riplinger, E. F. Valeev, and F. Neese

    J. Chem. Phys.   Vol. 146   page: 164105   2017

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  17. Multistate complete-active-space second-order perturbation theory based on density matrix renormalization group reference states Reviewed

    T. Yanai, M. Saitow, X.-G. Xiong, J. Chalupský, Y. Kurashige, S. Guo, and S. Sharma

    J. Chem. Theory Comput.   Vol. 13   page: 4829   2017

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  18. Influence of the choice of projection manifolds in the CASPT2 implementation Reviewed

    T. Yanai, Y. Kurashige, M. Saitow, J. Chalupský, R. Lindh, and P.-Å. Malmqvist

    Mol. Phys.   Vol. 115   page: 2077   2017

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  19. Psi4 1.1: An Open-Source Electronic Structure Program Empha- sizing Automation, Advanced Libraries, and Interoperability Reviewed

    R. M. Parrish, L. A. Burns, D. G. A. Smith, A. C. Simmonett, A. E. DePrince III, E. G. Ho- henstein, U. Bozkaya, A. Yu. Sokolov, R. Di Remigio, R. M. Richard, Jérôme F. Gonthier, A. M. James, H. R. McAlexander, A. Kumar, M. Saitow, X. Wang, B. P. Pritchard, P. Verma, H. F. Schaefer III, K. Patkowski, R. A. King, E. F. Valeev, F. A. Evangelista, J. M. Turney, T. D. Crawford and C. D. Sherrill

    J. Chem. Theory Comput   Vol. 13   page: 3185   2017

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  20. Decomposition of Intermolecular Interaction Energies within the Local Pair Natural Orbital Coupled Cluster Framework Reviewed

    W. B. Schneider, G. Bistoni, M. Sparta, M. Saitow, C. Riplinger, A. A. Auer, and F. Neese

    J. Chem. Theory Comput.   Vol. 12   page: 4778   2016

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  21. Density matrix renormalization group for ab initio Calculations and associated dynamic correlation methods: A review of theory and applications

    T. Yanai, Y. Kurashige, W. Mizukami, J. Chalupský, T. N. Lan, and M. Saitow

    Int. J. Quantum Chem.   Vol. 115   page: 283   2015

     More details

    Language:English  

  22. Fully Internally Contracted Multireference Configu- ration Interaction Theory Using Density Matrix Renormalization Group: A Reduced-Scaling Implementation Derived by Computer-Aided Tensor Factorization Reviewed

    M. Saitow, Y. Kurashige, and T. Yanai

    J. Chem. Theory Comput.   Vol. 11   page: 5120   2015

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  23. Improved description of the orbital relaxation effect by practical use of the self-energy Reviewed

    M. Saitow, T. Ida, and Y. Mochizuki

    Int. J. Quantum Chem.   Vol. 114   page: 577   2014

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  24. Radical O-O coupling reaction in diferrate- mediated water oxidation studied using multireference wave function theory Reviewed

    Y. Kurashige, M. Saitow, J. Chalupský, T. Yanai

    Phys. Chem. Chem. Phys.   Vol. 16   page: 11988   2014

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  25. Multireference configuration interaction theory using cumulant reconstruction with internal contraction of density matrix renormalization group wave function Reviewed

    M. Saitow, Y. Kurashige, and T. Yanai

    J. Chem. Phys.   Vol. 139   page: 044118   2013

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

  26. Excited state calculation for free-base and metalloporphyrins with the partially renormalized polarization propagator approach Reviewed

    M. Saitow, and Y. Mochizuki

    Chem. Phys. Lett.   Vol. 525   page: 144   2012

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

  27. Spin-adaptation of open-shell electron propagator theory Reviewed

    M. Saitow, T. Ida, and M. Mizuno

    Chem. Phys. Lett.   Vol. 486   page: 171   2010

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (scientific journal)  

▼display all

Presentations 3

  1. Reduced-Scaling Multireference Perturbation Thwories with Orthonormal Local Virtual Orbitals: An Extension to the Excited States Invited International conference

    Masaaki Saitow

    MPQCP-2024  2024.1.10 

     More details

    Event date: 2024.1

    Language:English   Presentation type:Oral presentation (invited, special)  

    Country:Japan  

  2. The PNO-based Reduce-scaling MRPT2 Theories based on Orthonormal Local Virtuals Invited

    Masaaki Saitow

    APATCC-2021  2023.2.21  APATCC

     More details

    Event date: 2023.2

    Language:English   Presentation type:Oral presentation (invited, special)  

    Venue:Quay Nhon, Vietnam  

  3. Multireference Wave Function Theories based on Local Pair-Natural Orbitals Invited International conference

    Masaaki Saitow

    ICT-HPCC22  2022.7.12  Chinese Academy of Science

     More details

    Language:English   Presentation type:Oral presentation (invited, special)  

Works 1

  1. ORCA Quantum Chemistry Program Suite

    2014

Research Project for Joint Research, Competitive Funding, etc. 2

  1. 高精度理論X線分光法による光合成過程における水分解反応機構の解明

    Grant number:22K05035  2022.4 - 2025.3

    科学研究費助成事業  基盤研究(C)

    齋藤雅明

      More details

    Authorship:Principal investigator  Grant type:Competitive

    Grant amount:\4160000 ( Direct Cost: \3200000 、 Indirect Cost:\960000 )

  2. Development of efficient and accurate electronic structure theory and its application to enzymatic reactions mediated by metalloprotein

    Grant number:20K15228  2020.4 - 2022.3

    Masaaki Saitow

      More details

    Authorship:Principal investigator  Grant type:Competitive

    Grant amount:\4290000 ( Direct Cost: \3300000 、 Indirect Cost:\990000 )

KAKENHI (Grants-in-Aid for Scientific Research) 2

  1. 高精度理論X線分光法による光合成過程における水分解反応機構の解明

    Grant number:22K05035  2022.4 - 2025.3

    日本学術振興会  科学研究費助成事業  基盤研究(C)

    齋藤雅明

      More details

    Authorship:Principal investigator  Grant type:Competitive

    Grant amount:\4160000 ( Direct Cost: \3200000 、 Indirect Cost:\960000 )

  2. Development of efficient and accurate electronic structure theory and its application to enzymatic reactions mediated by metalloprotein

    Grant number:20K15228  2020.4 - 2022.3

    Masaaki Saitow

      More details

    Authorship:Principal investigator  Grant type:Competitive

    Grant amount:\4290000 ( Direct Cost: \3300000 、 Indirect Cost:\990000 )

 

Teaching Experience (On-campus) 2

  1. 物理化学実験

    2022

  2. 化学演習

    2022