2022/10/01 更新

写真a

セイノ ジュンジ
清野 淳司
所属
理工学術院 大学院先進理工学研究科
職名
准教授(任期付)

学内研究所等

  • 2021年
    -
    2022年

    理工学術院総合研究所   兼任研究員

学歴

  • 2007年04月
    -
    2010年03月

    首都大学東京   理工学研究科   分子物質化学専攻  

  • 2005年04月
    -
    2007年03月

    首都大学東京   理学研究科   化学専攻  

  • 2000年04月
    -
    2005年03月

    東京都立大学   理学部   化学科  

学位

  • 首都大学東京   博士(理学)

経歴

  • 2021年04月
    -
    継続中

    早稲田大学   理工学術院 先進理工学部 化学・生命化学科   准教授

  • 2020年10月
    -
    2021年03月

    東京都立大学   理学部化学科   特任准教授

  • 2017年10月
    -
    2021年03月

    科学技術振興機構   さきがけ研究者

  • 2015年04月
    -
    2020年09月

    早稲田大学   理工学術院総合研究所   次席研究員(研究院講師)

  • 2012年04月
    -
    2015年03月

    日本学術振興会   特別研究員(PD)

  • 2010年04月
    -
    2012年03月

    早稲田大学   理工学術院   助手

▼全件表示

所属学協会

  •  
     
     

    理論化学会

  •  
     
     

    分子科学会

  •  
     
     

    日本化学会

  •  
     
     

    日本化学会情報化学部会

  •  
     
     

    日本コンピュータ化学会

 

研究分野

  • 基礎物理化学

研究キーワード

  • ケム・インフォマティクス

  • 相対論的量子化学

論文

  • Database-assisted local unitary transformation method for two-electron integrals in two-component relativistic calculations

    Chinami Takashima, Junji Seino, Hiromi Nakai

    CHEMICAL PHYSICS LETTERS   777  2021年08月  [査読有り]

     概要を見る

    This letter presents an efficient algorithm for local unitary transformation based on the spin-free infinite-order two-component relativistic method for the two-electron interaction, which is assisted by one-center relativistic two-electron integral (TEI) database. The database stores a set of TEIs, one for each element-basis set combination. The algorithm is numerically assessed for hydrogen halide chains, (HX)n (X = Cl and At), Aun, Ir(ppy)3, Pt3(C7H7)2(HCN)3, and PtCl2(NH3)2. The computational cost (time and memory size) at the Hartree-Fock level is lower than that of the conventional method, especially for small and medium-sized molecules.

    DOI

  • Implementation of Picture Change Corrected Density Functional Theory Based on Infinite-Order Two-Component Method to GAMESS Program

    Chinami Takashima, Junji Seino, Hiromi Nakai

    JOURNAL OF COMPUTER CHEMISTRY-JAPAN   19 ( 4 ) 128 - 130  2021年  [査読有り]

     概要を見る

    We implemented the picture change correction method for two-electron Coulomb interaction and density opeiator, which was based on the infinite-order two-component method with the local unitary transformation, to the GAMESS program. Numerical assessments for molecules containing heavy element confirmed the accuracies and efficiencies of the implementation. Furthermore, the comparison with several types of treatments indicated that whole picture change corrections of one- and two-electron operators and the density operator are necessary for accurate two-component density functional theory calculations.

    DOI

  • Machine-learned electron correlation model based on frozen core approximation

    Yasuhiro Ikabata, Ryo Fujisawa, Junji Seino, Takeshi Yoshikawa, Hiromi Nakai

    JOURNAL OF CHEMICAL PHYSICS   153 ( 18 )  2020年11月  [査読有り]

     概要を見る

    The machine-learned electron correlation (ML-EC) model is a regression model in the form of a density functional that reproduces the correlation energy density based on wavefunction theory. In a previous study [T. Nudejima et al., J. Chem. Phys. 151, 024104 (2019)], the ML-EC model was constructed using the correlation energy density from all-electron calculations with basis sets including core polarization functions. In this study, we applied the frozen core approximation (FCA) to the correlation energy density to reduce the computational cost of the response variable used in machine learning. The coupled cluster singles, doubles, and perturbative triples [CCSD(T)] correlation energy density obtained from a grid-based energy density analysis was analyzed within FCA and correlation-consistent basis sets without core polarization functions. The complete basis set (CBS) limit of the correlation energy density was obtained using the extrapolation and composite schemes. The CCSD(T)/CBS correlation energy densities based on these schemes showed reasonable behavior, indicating its appropriateness as a response variable. As expected, the computational time was significantly reduced, especially for systems containing elements with a large number of inner-shell electrons. Based on the density-to-density relationship, a large number of data (5 662 500 points), which were accumulated from 30 molecules, were sufficient to construct the ML-EC model. The valence-electron correlation energies and reaction energies calculated using the constructed model were in good agreement with the reference values, the latter of which were superior in accuracy to density functional calculations using 71 exchange-correlation functionals. The numerical results indicate that the FCA is useful for constructing a versatile model.

    DOI

  • Solvent Selection Scheme Using Machine Learning Based on Physicochemical Description of Solvent Molecules: Application to Cyclic Organometallic Reaction

    Mikito Fujinami, Hiroki Maekawara, Ryota Isshiki, Junji Seino, Junichiro Yamaguchi, Hiromi Nakai

    BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN   93 ( 7 ) 841 - 845  2020年07月  [査読有り]

     概要を見る

    A solvent selection scheme for optimization of reactions is proposed using machine learning, based on the numerical descriptions of solvent molecules. Twenty-eight key solvents were represented using 17 physicochemical descriptors. Clustering analysis results implied that the descriptor represents the chemical characteristics of the solvent molecules. During the assessment of an organometallic reaction system, the regression analysis indicated that learning even a small number of experimental results can be useful for identifying solvents that will produce high experimental yields. Observation of the regression coefficients, and both clustering and regression analysis, can be effective when selecting a solvent to be used for an experiment.

    DOI

  • Orbital-free density functional theory calculation applying semi-local machine-learned kinetic energy density functional and kinetic potential

    Fujinami Mikito, Kageyama Ryo, Seino Junji, Ikabata Yasuhiro, Nakai Hiromi

    Chemical Physics Letters   in press  2020年  [査読有り]

  • Quantum Chemical Reaction Prediction Method Based on Machine Learning

    Fujinami Mikito, Seino Junji, Nakai Hiromi

    Bulletin of the Chemical Society of Japan   in press  2020年  [査読有り]

  • Bond Energy Density Analysis Combined with Informatics Technique

    Hiromi Nakai, Junji Seino, Kairi Nakamura

    The Journal of Physical Chemistry A   123 ( 36 ) 7777 - 7784  2019年09月  [査読有り]

    DOI PubMed

  • Semi-local machine-learned kinetic energy density functional demonstrating smooth potential energy curves

    Chemical Physics Letters   734   136732  2019年08月  [査読有り]

  • Machine-learned electron correlation model based on correlation energy density at complete basis set limit

    Takuro Nudejima, Yasuhiro Ikabata, Junji Seino, Takeshi Yoshikawa, Hiromi Nakai

    The Journal of Chemical Physics   151 ( 2 ) 024104  2019年07月  [査読有り]

    DOI PubMed

  • Virtual Reaction Condition Optimization based on Machine Learning for a Small Number of Experiments in High-dimensional Continuous and Discrete Variables

    Chemistry Letters   48 ( 8 ) 961 - 964  2019年05月  [査読有り]

    DOI

  • Extension and acceleration of relativistic density functional theory based on transformed density operator

    Yasuhiro Ikabata, Takuro Oyama, Masao Hayami, Junji Seino, Hiromi Nakai

    The Journal of Chemical Physics   150 ( 16 ) 164104  2019年04月  [査読有り]

    DOI PubMed

  • RAQET: Large-scale two-component relativistic quantum chemistry program package

    Hayami Masao, Seino Junji, Nakajima Yuya, Nakano Masahiko, Ikabata Yasuhiro, Yoshikawa Takeshi, Oyama Takuro, Hiraga Kenta, Hirata So, Nakai Hiromi

    JOURNAL OF COMPUTATIONAL CHEMISTRY   39 ( 27 ) 2333 - 2344  2018年10月  [査読有り]

    DOI

  • Erratum: “Semi-local machine-learned kinetic energy density functional with third-order gradients of electron density” [J. Chem. Phys. 148, 241705 (2018)]

    Junji Seino, Ryo Kageyama, Mikito Fujinami, Yasuhiro Ikabata, Hiromi Nakai

    The Journal of Chemical Physics   149 ( 7 ) 079901 - 079901  2018年08月  [査読有り]

    DOI

  • Semi-local machine-learned kinetic energy density functional with third-order gradients of electron density

    Junji Seino, Ryo Kageyama, Mikito Fujinami, Yasuhiro Ikabata, Hiromi Nakai

    Journal of Chemical Physics   148 ( 24 )  2018年06月  [査読有り]

     概要を見る

    A semi-local kinetic energy density functional (KEDF) was constructed based on machine learning (ML). The present scheme adopts electron densities and their gradients up to third-order as the explanatory variables for ML and the Kohn-Sham (KS) kinetic energy density as the response variable in atoms and molecules. Numerical assessments of the present scheme were performed in atomic and molecular systems, including first- and second-period elements. The results of 37 conventional KEDFs with explicit formulae were also compared with those of the ML KEDF with an implicit formula. The inclusion of the higher order gradients reduces the deviation of the total kinetic energies from the KS calculations in a stepwise manner. Furthermore, our scheme with the third-order gradient resulted in the closest kinetic energies to the KS calculations out of the presented functionals.

    DOI

  • Semi-local machine-learned kinetic energy density functional with third-order gradients of electron density

    Junji Seino, Ryo Kageyama, Mikito Fujinami, Yasuhiro Ikabata, Hiromi Nakai

    The Journal of Chemical Physics   148   241705  2018年06月  [査読有り]

     概要を見る

    A semi-local kinetic energy density functional (KEDF) was constructed based on machine learning (ML). The present scheme adopts electron densities and their gradients up to third-order as the explanatory variables for ML and the Kohn-Sham (KS) kinetic energy density as the response variable in atoms and molecules. Numerical assessments of the present scheme were performed in atomic and molecular systems, including first- and second-period elements. The results of 37 conventional KEDFs with explicit formulae were also compared with those of the ML KEDF with an implicit formula. The inclusion of the higher order gradients reduces the deviation of the total kinetic energies from the KS calculations in a stepwise manner. Furthermore, our scheme with the third-order gradient resulted in the closest kinetic energies to the KS calculations out of the presented functionals.

    DOI

  • Gauge-origin independent formalism of two-component relativistic framework based on unitary transformation in nuclear magnetic shielding constant

    Masao Hayami, Junji Seino, Hiromi Nakai

    Journal of Chemical Physics   148 ( 11 )  2018年03月  [査読有り]

     概要を見る

    This article proposes a gauge-origin independent formalism of the nuclear magnetic shielding constant in the two-component relativistic framework based on the unitary transformation. The proposed scheme introduces the gauge factor and the unitary transformation into the atomic orbitals. The two-component relativistic equation is formulated by block-diagonalizing the Dirac Hamiltonian together with gauge factors. This formulation is available for arbitrary relativistic unitary transformations. Then, the infinite-order Douglas-Kroll-Hess (IODKH) transformation is applied to the present formulation. Next, the analytical derivatives of the IODKH Hamiltonian for the evaluation of the nuclear magnetic shielding constant are derived. Results obtained from the numerical assessments demonstrate that the present formulation removes the gauge-origin dependence completely. Furthermore, the formulation with the IODKH transformation gives results that are close to those in four-component and other two-component relativistic schemes.

    DOI

  • Derivative of electron repulsion integral using accompanying coordinate expansion and transferred recurrence relation method for long contraction and high angular momentum

    Masao Hayami, Junji Seino, Hiromi Nakai

    International Journal of Quantum Chemistry   118 ( 16 )  2018年  [査読有り]

    DOI

  • Computerized Implementation of Higher-Order Electron-Correlation Methods and Their Linear-Scaling Divide-and-Conquer Extensions

    Masahiko Nakano, Takeshi Yoshikawa, So Hirata, Junji Seino, Hiromi Nakai

    JOURNAL OF COMPUTATIONAL CHEMISTRY   38 ( 29 ) 2520 - 2527  2017年11月  [査読有り]

     概要を見る

    We have implemented a linear-scaling divide-and-conquer (DC)-based higher-order coupled-cluster (CC) and Moller-Plesset perturbation theories (MPPT) as well as their combinations automatically by means of the tensor contraction engine, which is a computerized symbolic algebra system. The DC-based energy expressions of the standard CC and MPPT methods and the CC methods augmented with a perturbation correction were proposed for up to high excitation orders [e.g., CCSDTQ, MP4, and CCSD(2)(TQ)]. The numerical assessment for hydrogen halide chains, polyene chains, and first coordination sphere (C1) model of photoactive yellow protein has revealed that the DC-based correlation methods provide reliable correlation energies with significantly less computational cost than that of the conventional implementations. (C) 2017 Wiley Periodicals, Inc.

    DOI

  • Relativistic density functional theory with picture-change corrected electron density based on infinite-order Douglas-Kroll-Hess method

    Takuro Oyama, Yasuhiro Ikabata, Junji Seino, Hiromi Nakai

    CHEMICAL PHYSICS LETTERS   680   37 - 43  2017年07月  [査読有り]

     概要を見る

    This Letter proposes a density functional treatment based on the two-component relativistic scheme at the infinite-order Douglas-Kroll-Hess (IODKH) level. The exchange-correlation energy and potential are calculated using the electron density based on the picture-change corrected density operator transformed by the IODKH method. Numerical assessments indicated that the picture-change uncorrected density functional terms generate significant errors, on the order of hartree for heavy atoms. The present scheme was found to reproduce the energetics in the four-component treatment with high accuracy. (C) 2017 Elsevier B.V. All rights reserved.

    DOI

  • Development of spin-dependent relativistic open-shell Hartree–Fock theory with time-reversal symmetry (II): The restricted open-shell approach

    Masahikok Nakano, Ryota Nakamura, Junji Seino, Hiromi Nakai

    INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY   117 ( 10 ) e25366  2017年05月  [査読有り]

    DOI

  • Universal formulation of second-order generalized Moller-Plesset perturbation theory for a spin-dependent two-component relativistic many-electron Hamiltonian

    Masahiko Nakano, Junji Seino, Hiromi Nakai

    CHEMICAL PHYSICS LETTERS   675   137 - 144  2017年05月  [査読有り]

     概要を見る

    We have derived and implemented a universal formulation of the second-order generalized MollerPlesset perturbation theory (GMP2) for spin-dependent (SD) two-component relativistic many-electron Hamiltonians, such as the infinite-order Douglas-Kroll-Hess Hamiltonian for many-electron systems, which is denoted as IODKH/IODKH. Numerical assessments for He- and Ne-like atoms and 16 diatomic molecules show that the MP2 correlation energies with IODKH/IODKH agree well with those calculated with the four-component Dirac-Coulomb (DC) Hamiltonian, indicating a systematic improvement on the inclusion of relativistic two-electron terms. The present MP2 scheme for IODKH/IODKH is demonstrated to be computationally more efficient than that for DC. (c) 2017 Elsevier B.V. All rights reserved.

    DOI

  • Development of spin-dependent relativistic open-shell Hartree-Fock theory with time-reversal symmetry (I): The unrestricted approach

    Masahiko Nakano, Junji Seino, Hiromi Nakai

    INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY   117 ( 10 ) e25356  2017年05月  [査読有り]

     概要を見る

    An open-shell Hartree-Fock (HF) theory for spin-dependent, two-component relativistic calculations, termed the Kramers-unrestricted HF (KUHF) method, is developed. The present KUHF method, which is formulated as a relativistic counterpart of nonrelativistic UHF, is based on quaternion algebra and partly uses time-reversal symmetry. The fundamental characteristics of KUHF are discussed in this study. From numerical assessments, it was revealed that KUHF gives a corresponding solution to nonrelativistic UHF; furthermore, KUHF properly describes spin-orbit interactions. In addition, KUHF can improve the self-consistent field convergence behavior in spin-dependent calculations, for example, for f-block elements.

    DOI

  • Relativistic effect on enthalpy of formation for transition-metal complexes

    Yuya Nakajima, Junji Seino, Hiromi Nakai

    CHEMICAL PHYSICS LETTERS   673   24 - 29  2017年04月  [査読有り]

     概要を見る

    This Letter examines the enthalpy of formation for 12 transition metal diatomic molecules and 23 transition metal complexes from the viewpoint of effect of the relativistic effect by using the infinite-order Douglas-Kroll-Hess method with the local unitary transformation and three types of pseudopotentials for several levels of theory. The spin-orbit effect contribution to the enthalpy of formation is more than 10 kcal/mol for third transition metal complexes. Frozen orbital approximation at the outermost orbitals in pseudopotential methods shows a contribution to the enthalpy of formation that is more than two times larger than those of inner core orbitals. (C) 2017 Elsevier B.V. All rights reserved.

    DOI

  • Unveiling a New Aspect of Simple Arylboronic Esters: Long-Lived Room-Temperature Phosphorescence from Heavy-Atom-Free Molecules

    Yoshiaki Shoji, Yasuhiro Ikabata, Qi Wang, Daisuke Nemoto, Atsushi Sakamoto, Naoki Tanaka, Junji Seino, Hiromi Nakai, Takanori Fukushima

    JOURNAL OF THE AMERICAN CHEMICAL SOCIETY   139 ( 7 ) 2728 - 2733  2017年02月  [査読有り]

     概要を見る

    Arylboronic esters can be used as versatile reagents in organic synthesis, as represented by Suzuki Miyaura cross-coupling. Here we report a serendipitous finding that simple arylboronic esters are phosphorescent in the solid state at room temperature with a lifetime on the order of several seconds. The phosphorescence properties of arylboronic esters are remarkable in light of the general notion that phosphorescent organic molecules require heavy atoms and/or carbonyl groups for the efficient generation of a triplet excited state. Theoretical calculations on phenylboronic acid pinacol ester indicated that this molecule undergoes an out-of-plane distortion at the (pinacol)B-C-ipso moiety in the T-1 excited state, which is responsible for its phosphorescence. A compound survey with 19 arylboron compounds suggested that the phosphorescence properties might be determined by solid-state molecular packing rather than by the patterns and numbers of boron substituents on the aryl units. The present finding may update the general notion of phosphorescent organic molecules.

    DOI

  • Development of Reaction Prediction Scheme Based on Machine Learning with Quantum Chemical Descriptors

    Mikito Fujinami, Junji Seino, Hiromi Nakai

    Journal of Computer Chemistry, Japan   15   63  2016年10月  [査読有り]

    DOI

  • Implementation of Efficient Two-component Relativistic Method Using Local Unitary Transformation to GAMESS Program

    Yuya Nakajima, Junji Seino, Michael W. Schmidt, Hiromi Nakai

    Journal of Computer Chemistry, Japan   15   68 - 70  2016年10月  [査読有り]

    DOI

  • Relativistic frozen core potential scheme with relaxation of core electrons

    Yuya Nakajima, Junji Seino, Masao Hayami, Hiromi Nakai

    CHEMICAL PHYSICS LETTERS   663   97 - 103  2016年10月  [査読有り]

     概要を見る

    This letter proposes a relaxation scheme for core electrons based on the frozen core potential method at the infinite-order Douglas-Kroll-Hess level, called FCP-CR. The core electrons are self-consistently relaxed using frozen molecular valence potentials after the valence SCF calculation is performed. The efficiency of FCP-CR is confirmed by calculations of gold clusters. Furthermore, FCP-CR reproduces the results of the all-electron method for the energies of coinage metal dimers and the core ionization energies and core level shifts of vinyl acetate and three tungsten complexes at the Hartree Fock and/or symmetry-adapted cluster configuration interaction levels. (C) 2016 Elsevier B.V. All rights reserved.

    DOI

  • Informatics-Based Energy Fitting Scheme for Correlation Energy at Complete Basis Set Limit

    Junji Seino, Hiromi Nakai

    JOURNAL OF COMPUTATIONAL CHEMISTRY   37 ( 25 ) 2304 - 2315  2016年09月  [査読有り]

     概要を見る

    Energy fitting schemes based on informatics techniques using hierarchical basis sets with small cardinal numbers were numerically investigated to estimate correlation energies at the complete basis set limits. Numerical validations confirmed that the conventional two-point extrapolation models can be unified into a simple formula with optimal parameters obtained by the same test sets. The extrapolation model was extended to two-point fitting models by a relaxation of the relationship between the extrapolation coefficients or a change of the fitting formula. Furthermore, n-scheme fitting models were developed by the combinations of results calculated at several theory levels and basis sets to compensate for the deficiencies in the fitting model at one level of theory. Systematic assessments on the Gaussian-3X and Gaussian-2 sets revealed that the fitting models drastically reduced errors with equal or smaller computational effort. (c) 2016 Wiley Periodicals, Inc.

    DOI

  • Assessment of self-consistent field convergence in spin-dependent relativistic calculations

    Masahiko Nakano, Junji Seino, Hiromi Nakai

    CHEMICAL PHYSICS LETTERS   657   65 - 71  2016年07月  [査読有り]

     概要を見る

    This Letter assesses the self-consistent field (SCF) convergence behavior in the generalized Hartree-Fock (GHF) method. Four acceleration algorithms were implemented for efficient SCF convergence in the GHF method: the damping algorithm, the conventional direct inversion in the iterative subspace (DIIS), the energy-DIIS (EDIIS), and a combination of DIIS and EDIIS. Four different systems with varying complexity were used to investigate the SCF convergence using these algorithms, ranging from atomic systems to metal complexes. The numerical assessments demonstrated the effectiveness of a combination of DIIS and EDIIS for GHF calculations in comparison with the other discussed algorithms. (C) 2016 Elsevier B.V. All rights reserved.

    DOI

  • Implementation of Analytical Energy Gradient of Spin-Dependent General Hartree-Fock Method Based on the Infinite-Order Douglas-Kroll-Hess Relativistic Hamiltonian with Local Unitary Transformation

    Yuya Nakajima, Junji Seino, Hiromi Nakai

    JOURNAL OF CHEMICAL THEORY AND COMPUTATION   12 ( 5 ) 2181 - 2190  2016年05月  [査読有り]

     概要を見る

    An analytical energy gradient for the spin dependent general Hartree-Fock method based on the infinite-order Douglas-Kroll-Hess (IODKH) method was developed. To treat realistic systems, the local unitary transformation (LUT) scheme was employed both in energy and energy gradient calculations. The present energy gradient method was numerically assessed to investigate the accuracy in several diatomic molecules containing fifth- and sixth-period elements and to examine the efficiency in one-, two,, and three-dimensional silver clusters. To arrive at a practical calculation, we also determined the geometrical-parameters of fac-tris(2-phenylpyridine)iridium and investigated the efficiency. The numerical results confirmed that the present method describes highly accurate relativistic effect with high efficiency. The present method can be a powerful scheme for determining geometries of large molecules, including heavy-element atoms.

    DOI

  • 量子化学計算と群知能を用いたアミン-CO2系反応に対する反応シミュレータの開発

    長門 澄香, 寺西 慶, 清野 淳司, 中井 浩巳

    ケモインフォマティクス討論会予稿集   2016 ( 0 ) P12  2016年  [査読有り]

     概要を見る

    地球温暖化の原因であるCO2の排出量を削減する手段としてCO2回収貯留(CCS)技術が注目されている。このCCS技術の中でも、広く用いられている化学吸収法は、アミンなど塩基性吸収液へCO2を吸収させる分離過程と加熱によって高濃度のCO2を放散させる回収過程からなる。これまでCO2<br>吸収時に要するエネルギーの削減を目指してアミンの研究・開発が行われている。CO2吸収効率の良いアミンを探す上で、各アミンについてその化学種濃度の経時変化を予測することは重要である。本研究ではアミン-CO2反応中の素反応を考慮し、群知能を用いることで実験のローディング依存性から平衡定数を予測する反応シミュレータを開発した。またその平衡定数を量子化学計算による反応自由エネルギーから見積もることで、化学種濃度のローディング依存性の予測も行い、広く1級から3級アミンまで扱えるように拡張した。

    DOI CiNii

  • 量子化学計算とインフォマティクス技術を用いた反応予測システムの開発

    藤波 美起登, 清野 淳司, 中井 浩巳

    ケモインフォマティクス討論会予稿集   2016 ( 0 ) O1  2016年  [査読有り]

     概要を見る

    これまで、コンピュータを用いて反応物から得られる生成物を予測するシステムが多数開発されてきた。しかし、化学反応の複雑さをコンピュータが表現することは難しく、未だ実験化学者に広く利用されるシステムの開発には至っていない。近年、分子のトポロジカルな情報を中心的な記述子として、機械学習を有機化学反応の予測に応用したシステムが優れた予測能を示した。しかしこの手法は、金属種を含む反応など、分子の立体的構造や電子状態が生成物を左右する反応の予測が困難であると考えられる。そこで本研究では、あらゆる化学種に対する反応予測を目指して、量子化学計算により得られる情報を記述子として機械学習を用いるシステムを開発した。本手法は基本的な有機化学の極性反応およびラジカル反応に対して既存手法と同程度の予測精度を示した。本発表では、本手法の詳細および予測精度の量子化学計算条件に対する依存性について検証した結果を報告する。

    DOI CiNii

  • An Ab Initio Study of Nuclear Volume Effects for Isotope Fractionations Using Two-Component Relativistic Methods

    Keisuke Nemoto, Minori Abe, Junji Seino, Masahiko Hada

    JOURNAL OF COMPUTATIONAL CHEMISTRY   36 ( 11 ) 816 - 820  2015年04月  [査読有り]

     概要を見る

    We investigate the accuracy of two-component Douglas-Kroll-Hess (DKH) methods in calculations of the nuclear volume term ( lnK(nv)) in the isotope fractionation coefficient. lnK(nv) is a main term in the chemical equilibrium constant for isotope exchange reactions in heavy element. Previous work based on the four-component method reasonably reproduced experimental lnK(nv) values of uranium isotope exchange. In this work, we compared uranium reaction lnK(nv) values obtained from the two-component and four-component methods. We find that both higher-order relativistic interactions and spin-orbit interactions are essential for quantitative description of lnK(nv). The best alternative is the infinite-order Douglas-Kroll-Hess method with infinite-order spin-orbit interactions for the one-electron term and atomic-mean-field spin-same-orbit interaction for the two-electron term (IODKH-IOSO-MFSO). This approach provides almost equivalent results for the four-component method, while being 30 times faster. The IODKH-IOSO-MFSO methodology should pave the way toward computing larger and more general molecules beyond the four-component method limits. (c) 2015 Wiley Periodicals, Inc.

    DOI

  • Accompanying coordinate expansion and recurrence relation method using a transfer relation scheme for electron repulsion integrals with high angular momenta and long contractions

    Hayami, Masao, Seino, Junji, Nakai, Hiromi

    Journal of Chemical Physics   142 ( 20 )  2015年  [査読有り]

     概要を見る

    :An efficient algorithm for the rapid evaluation of electron repulsion integrals is proposed. The present method, denoted by accompanying coordinate expansion and transferred recurrence relation (ACE-TRR), is constructed using a transfer relation scheme based on the accompanying coordinate expansion and recurrence relation method. Furthermore, the ACE-TRR algorithm is extended for the general-contraction basis sets. Numerical assessments clarify the efficiency of the ACE-TRR method for the systems including heavy elements, whose orbitals have long contractions and high angular momenta, such as f- and g-orbitals.

    DOI PubMed

  • インフォマティクス技術を用いた完全基底関数極限における電子相関エネルギーの評価

    清野 淳司, 大越 昌樹, 中井 浩巳

    ケモインフォマティクス討論会予稿集   2015 ( 0 ) 24 - 25  2015年  [査読有り]

     概要を見る

    完全基底関数極限における高精度な電子相関を含んだ電子相関エネルギーを高効率に算出することは化学的精度(1 kcal/mol以内)での量子化学計算を実現するために重要である。これまで種々の電子相関エネルギーの完全基底関数極限への外挿手法や、幾つかの計算レベル・基底関数でのエネルギーを組み合わせた複合法が提案されてきた。本研究では情報学手法を用いてより効率的に、完全基底関数極限におけるCCSD(T)レベルの電子相関エネルギーを算出する手法を提案する。

    DOI CiNii

  • Large-Scale Two-Component Relativistic Quantum-Chemical Theory: Combination of the Infinite-Order Douglas-Kroll-Hess Method with the Local Unitary Transformation Scheme and the Divide-and-Conquer Method

    Seino, Junji, Nakai, Hiromi

    International Journal of Quantum Chemistry   115 ( 5 ) 253 - 257  2015年  [査読有り]

    DOI

  • Accompanying coordinate expansion and recurrence relation method using a transfer relation scheme for electron repulsion integrals with high angular momenta and long contractions

    Hayami, Masao, Seino, Junji, Nakai, Hiromi

    Journal of Chemical Physics   142 ( 20 )  2015年  [査読有り]

    DOI

  • Extension of Accompanying Coordinate Expansion and Recurrence Relation Method for General-Contraction Basis Sets

    Masao Hayami, Junji Seino, Hiromi Nakai

    JOURNAL OF COMPUTATIONAL CHEMISTRY   35 ( 20 ) 1517 - 1527  2014年07月  [査読有り]

     概要を見る

    An algorithm of the accompanying coordinate expansion and recurrence relation (ACE-RR), which is used for the rapid evaluation of the electron repulsion integral (ERI), has been extended to the general-contraction (GC) scheme. The present algorithm, denoted by GC-ACE-RR, is designed for molecular calculations including heavy elements, whose orbitals consist of many primitive functions with and without higher angular momentum such as d- and f-orbitals. The performance of GC-ACE-RR was assessed for (ss vertical bar ss), (pp vertical bar pp), (dd vertical bar dd), and (ff vertical bar ff)-type ERIs in terms of contraction length and the number of GC orbitals. The present algorithm was found to reduce the central processing unit time compared with the ACE-RR algorithm, especially for higher angular momentum and highly contracted orbitals. Compared with HONDOPLUS and GAMESS program packages, GC-ACE-RR computations for ERIs of three-dimensional gold clusters Au-n (n = 1, 2, . . . , 10, 15, 20, and 25) are more than 10 times faster. (C) 2014 Wiley Periodicals, Inc.

    DOI

  • Extension of Accompanying Coordinate Expansion and Recurrence Relation Method for General-Contraction Basis Sets

    Hayami, Masao, Seino, Junji, Nakai, Hiromi

    Journal of Computational Chemistry   35 ( 20 )  2014年  [査読有り]

     概要を見る

    :An algorithm of the accompanying coordinate expansion and recurrence relation (ACE-RR), which is used for the rapid evaluation of the electron repulsion integral (ERI), has been extended to the general-contraction (GC) scheme. The present algorithm, denoted by GC-ACE-RR, is designed for molecular calculations including heavy elements, whose orbitals consist of many primitive functions with and without higher angular momentum such as d- and f-orbitals. The performance of GC-ACE-RR was assessed for (ss|ss)-, (pp|pp)-, (dd|dd)-, and (ff|ff)-type ERIs in terms of contraction length and the number of GC orbitals. The present algorithm was found to reduce the central processing unit time compared with the ACE-RR algorithm, especially for higher angular momentum and highly contracted orbitals. Compared with HONDOPLUS and GAMESS program packages, GC-ACE-RR computations for ERIs of three-dimensional gold clusters Aun (n = 1, 2, …, 10, 15, 20, and 25) are more than 10 times faster.

    DOI

  • Large-scale and highly accurate relativistic quantum-chemical scheme: toward establishment of theoretical foundation for element strategy

    Junji Seino, Hiromi Nakai

    Journal of Computer Chemistry, Japan   13 ( 1 ) 1 - 17  2014年  [査読有り]

     概要を見る

    本稿では,大規模な重元素化合物を高効率・高精度に計算するための理論を取り上げる.まず相対論的量子化学の現状を概観し,それを踏まえて目的を遂行するためにどの部分を考察しなければならないのかを述べたい.次にこれらの問題点を解決すべく,著者らが開発した高効率・高精度な2成分相対論計算手法,無限次Douglas-Kroll-Hess変換に基づく局所ユニタリー変換法の理論について解説し,数値検証を行うことで有用性を示す.さらに本手法を分割統治法へと拡張することにより,計算全体の線形スケーリングを達成する手法となることを示す.本手法に基づけば,非相対論と同等の計算コストで (スピン非依存の) 4成分相対論と同程度の精度を与えることができるため,従来の非相対論的なSchrödinger方程式から相対論的なDirac方程式へのパラダイムシフトが可能となる.

    DOI CiNii

  • Frozen core potential scheme with a relativistic electronic Hamiltonian: Theoretical connection between the model potential and all-electron treatments

    Junji Seino, Moto Tarumi, Hiromi Nakai

    CHEMICAL PHYSICS LETTERS   592   341 - 348  2014年01月  [査読有り]

     概要を見る

    This Letter proposes an accurate scheme using frozen core orbitals, called the frozen core potential (FCP) method, to theoretically connect model potential calculations to all-electron (AE) ones. The present scheme is based on the Huzinaga-Cantu equation combined with spin-free relativistic Douglas-KrollHess Hamiltonians. The local unitary transformation scheme for efficiently constructing the Hamiltonian produces a seamless extension to the FCP method in a relativistic framework. Numerical applications to coinage diatomic molecules illustrate the high accuracy of this FCP method, as compared to AE calculations. Furthermore, the efficiency of the FCP method is also confirmed by these calculations. (C) 2014 Elsevier B.V. All rights reserved.

    DOI

  • Analytical energy gradient based on spin-free infinite-order Douglas-Kroll-Hess method with local unitary transformation

    Nakajima, Yuya, Seino, Junji, Nakai, Hiromi

    Journal of Chemical Physics   139 ( 24 )  2013年  [査読有り]

     概要を見る

    :In this study, the analytical energy gradient for the spin-free infinite-order Douglas-Kroll-Hess (IODKH) method at the levels of the Hartree-Fock (HF), density functional theory (DFT), and second-order Møller-Plesset perturbation theory (MP2) is developed. Furthermore, adopting the local unitary transformation (LUT) scheme for the IODKH method improves the efficiency in computation of the analytical energy gradient. Numerical assessments of the present gradient method are performed at the HF, DFT, and MP2 levels for the IODKH with and without the LUT scheme. The accuracies are examined for diatomic molecules such as hydrogen halides, halogen dimers, coinage metal (Cu, Ag, and Au) halides, and coinage metal dimers, and 20 metal complexes, including the fourth-sixth row transition metals. In addition, the efficiencies are investigated for one-, two-, and three-dimensional silver clusters. The numerical results confirm the accuracy and efficiency of the present method.

    DOI

  • Local unitary transformation method toward practical electron correlation calculations with scalar relativistic effect in large-scale molecules.

    Seino Junji, Nakai Hiromi

    Local unitary transformation method toward practical electron correlation calculations with scalar relativistic effect in large-scale molecules.   139 ( 3 )  2013年  [査読有り]

     概要を見る

    :In order to perform practical electron correlation calculations, the local unitary transformation (LUT) scheme at the spin-free infinite-order Douglas-Kroll-Hess (IODKH) level [J. Seino and H. Nakai, J. Chem. Phys. 136, 244102 (2012); and ibid. 137, 144101 (2012)], which is based on the locality of relativistic effects, has been combined with the linear-scaling divide-and-conquer (DC)-based Hartree-Fock (HF) and electron correlation methods, such as the second-order Mo̸ller-Plesset (MP2) and the coupled cluster theories with single and double excitations (CCSD). Numerical applications in hydrogen halide molecules, (HX)n (X = F, Cl, Br, and I), coinage metal chain systems, Mn (M = Cu and Ag), and platinum-terminated polyynediyl chain, trans,trans-{(p-CH3C6H4)3P}2(C6H5)Pt(C≡C)4Pt(C6H5){(p-CH3C6H4)3P}2, clarified that the present methods, namely DC-HF, MP2, and CCSD with the LUT-IODKH Hamiltonian, reproduce the results obtained using conventional methods with small computational costs. The combination of both LUT and DC techniques could be the first approach that achieves overall quasi-linear-scaling with a small prefactor for relativistic electron correlation calculations.

    DOI

  • Local unitary transformation method toward practical electron correlation calculations with scalar relativistic effect in large-scale molecules

    Seino, Junji, Nakai, Hiromi

    Journal of Chemical Physics   139 ( 3 )  2013年  [査読有り]

    DOI

  • Analytical energy gradient based on spin-free infinite-order Douglas-Kroll-Hess method with local unitary transformation

    Nakajima, Yuya, Seino, Junji, Nakai, Hiromi

    Journal of Chemical Physics   139 ( 24 )  2013年  [査読有り]

    DOI

  • Local unitary transformation method for large-scale two-component relativistic calculations. II. Extension to two-electron Coulomb interaction

    Junji Seino, Hiromi Nakai

    JOURNAL OF CHEMICAL PHYSICS   137 ( 14 )  2012年10月  [査読有り]

     概要を見る

    The local unitary transformation (LUT) scheme at the spin-free infinite-order Douglas-Kroll-Hess (IODKH) level [J. Seino and H. Nakai, J. Chem. Phys. 136, 244102 (2012)], which is based on the locality of relativistic effects, has been extended to a four-component Dirac-Coulomb Hamiltonian. In the previous study, the LUT scheme was applied only to a one-particle IODKH Hamiltonian with non-relativistic two-electron Coulomb interaction, termed IODKH/C. The current study extends the LUT scheme to a two-particle IODKH Hamiltonian as well as one-particle one, termed IODKH/IODKH, which has been a real bottleneck in numerical calculation. The LUT scheme with the IODKH/IODKH Hamiltonian was numerically assessed in the diatomic molecules HX and X-2 and hydrogen halide molecules, (HX)(n) (X = F, Cl, Br, and I). The total Hartree-Fock energies calculated by the LUT method agree well with conventional IODKH/IODKH results. The computational cost of the LUT method is reduced drastically compared with that of the conventional method. In addition, the LUT method achieves linear-scaling with respect to the system size and a small prefactor. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4757263]

    DOI

  • Local unitary transformation method for large-scale two-component relativistic calculations: Case for a one-electron Dirac Hamiltonian

    Junji Seino, Hiromi Nakai

    JOURNAL OF CHEMICAL PHYSICS   136 ( 24 )  2012年06月  [査読有り]

     概要を見る

    An accurate and efficient scheme for two-component relativistic calculations at the spin-free infinite-order Douglas-Kroll-Hess (IODKH) level is presented. The present scheme, termed local unitary transformation (LUT), is based on the locality of the relativistic effect. Numerical assessments of the LUT scheme were performed in diatomic molecules such as HX and X-2 (X = F, Cl, Br, I, and At) and hydrogen halide clusters, (HX)(n) (X = F, Cl, Br, and I). Total energies obtained by the LUT method agree well with conventional IODKH results. The computational costs of the LUT method are drastically lower than those of conventional methods since in the former there is linear-scaling with respect to the system size and a small prefactor. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4729463]

    DOI

  • Local unitary transformation method for large-scale two-component relativistic calculations. II. Extension to two-electron Coulomb interaction.

    Seino Junji, Nakai Hiromi

    Local unitary transformation method for large-scale two-component relativistic calculations. II. Extension to two-electron Coulomb interaction.   137 ( 14 )  2012年  [査読有り]

     概要を見る

    :The local unitary transformation (LUT) scheme at the spin-free infinite-order Douglas-Kroll-Hess (IODKH) level [J. Seino and H. Nakai, J. Chem. Phys. 136, 244102 (2012)], which is based on the locality of relativistic effects, has been extended to a four-component Dirac-Coulomb Hamiltonian. In the previous study, the LUT scheme was applied only to a one-particle IODKH Hamiltonian with non-relativistic two-electron Coulomb interaction, termed IODKH/C. The current study extends the LUT scheme to a two-particle IODKH Hamiltonian as well as one-particle one, termed IODKH/IODKH, which has been a real bottleneck in numerical calculation. The LUT scheme with the IODKH/IODKH Hamiltonian was numerically assessed in the diatomic molecules HX and X(2) and hydrogen halide molecules, (HX)(n) (X = F, Cl, Br, and I). The total Hartree-Fock energies calculated by the LUT method agree well with conventional IODKH/IODKH results. The computational cost of the LUT method is reduced drastically compared with that of the conventional method. In addition, the LUT method achieves linear-scaling with respect to the system size and a small prefactor.

    DOI

  • Local unitary transformation method for large-scale two-component relativistic calculations: case for a one-electron Dirac Hamiltonian.

    Seino Junji, Nakai Hiromi

    Local unitary transformation method for large-scale two-component relativistic calculations: case for a one-electron Dirac Hamiltonian.   136 ( 24 )  2012年  [査読有り]

     概要を見る

    :An accurate and efficient scheme for two-component relativistic calculations at the spin-free infinite-order Douglas-Kroll-Hess (IODKH) level is presented. The present scheme, termed local unitary transformation (LUT), is based on the locality of the relativistic effect. Numerical assessments of the LUT scheme were performed in diatomic molecules such as HX and X(2) (X = F, Cl, Br, I, and At) and hydrogen halide clusters, (HX)(n) (X = F, Cl, Br, and I). Total energies obtained by the LUT method agree well with conventional IODKH results. The computational costs of the LUT method are drastically lower than those of conventional methods since in the former there is linear-scaling with respect to the system size and a small prefactor.

    DOI

  • Magnetic shielding constants calculated by the infinite-order Douglas-Kroll-Hess method with electron-electron relativistic corrections

    Junji Seino, Masahiko Hada

    JOURNAL OF CHEMICAL PHYSICS   132 ( 17 )  2010年05月  [査読有り]

     概要を見る

    We presented a two-component relativistic quantum-chemical theory for magnetic shielding constants, which is based on the infinite-order Douglas-Kroll (IODK) transformation. Two-electron relativistic corrections were also generated using the IODK transformation, although negligibly small terms were discarded. The use of small-component basis functions was completely excluded from the present theory. We examined the combination of the levels of relativistic one- and two-electron terms and magnetic interaction terms using the first-order Foldy-Wouthuysen (FW1), the second-order Douglas-Kroll (DK2), and the infinite-order Douglas-Kroll (IODK) transformations, as well as the lowest-order (c(-2)) Breit-Pauli approximation. We calculated the magnetic shielding constants of several closed-shell atoms using the FW1, DK2, IODK, and Breit-Pauli Hamiltonians. The IODK Hamiltonian reproduced well the results calculated by the four-component Dirac-Fock-Coulomb theory: The maximum deviation is only about 2.2%. We found that the accuracy of the magnetic shielding constants is strongly affected by the relativistic treatments of one-electron magnetic interaction, while the effect of the two-component two-electron relativistic corrections is relatively small. We also discussed the picture change effect on magnetic operators. (c) 2010 American Institute of Physics. [doi: 10.1063/1.3413529]

    DOI

  • Expectation values in two-component relativistic theories

    Junji Seino, Wataru Uesugi, Masahiko Hada

    JOURNAL OF CHEMICAL PHYSICS   132 ( 16 )  2010年04月  [査読有り]

     概要を見る

    We examined numerically the equivalence between the expectation values calculated by the four-component wave function and those calculated by the two-component wave functions generated by the infinite-order Douglas-Kroll (IODK) transformation. We showed the expectation values &lt; r(-1)&gt; and &lt;delta(r-R)&gt; in several closed-shell atoms using the so-called picture-changed 2 x 2 operators at some levels of approximation. The effect of the two-electron Coulomb term was also discussed. The numerical results indicated that the accuracy of &lt; r(-1)&gt; mainly depends on the level of the wave functions, while that of &lt;delta(r-R)&gt; is affected by the accuracy of both the wave functions and the picture-changed operators. As expected, the picture-changed operators and the IODK wave functions generate essentially equivalent expectation values in comparison with those calculated by the four-component Dirac-type method. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3397070]

    DOI

  • Examination of accuracy of electron-electron Coulomb interactions in two-component relativistic methods

    Junji Seino, Masahiko Hada

    CHEMICAL PHYSICS LETTERS   461 ( 4-6 ) 327 - 331  2008年08月  [査読有り]

     概要を見る

    We examined the accuracy of two-component quantum-chemical methods, focusing on relativistic treatments of the electron-electron Coulomb interaction. We observed SCF energies, orbital energies, and spin-orbit splittings of He-like and noble-gas atoms up to Uuo (atomic number 118). These were calculated by using either the two-electron term generated by the first-order Foldy-Wouthuysen (2e-FW1) or the infinite-order Douglas-Kroll-Hess (2e-IODKH) transformation, both of which are incorporated with the one-electron terms generated by the IODKH transformation. The 2e-FW1 term was much superior to the lowest-order (c (2)) two-electron Breit-Pauli correction, and the 2e-IODKH term gave energies essentially equivalent to four-component Dirac-Fock/Coulomb energies. (C) 2008 Elsevier B. V. All rights reserved.

    DOI

  • Applicability of the lowest-order two-electron Breit-Pauli relativistic correction in many-electron heavy and super-heavy elements

    Junji Seino, Masahiko Hada

    CHEMICAL PHYSICS LETTERS   442 ( 1-3 ) 134 - 139  2007年07月  [査読有り]

     概要を見る

    The applicability of the lowest-order two-electron Breit-Pauli (2e-BP) relativistic correction incorporated with the infinite-order Foldy-Wouthuysen (IOFW) transformation was examined in heavy and super-heavy elements. Comparing with the non-relativistic Coulomb repulsion term, in cases of moderately heavy noble-gas atoms (He to Ar), the 2e-BP correction gave the SCF energies practically equivalent to those obtained with the Dirac-Fock/Coulomb method. The spin-orbit splittings were also corrected reasonably. On the other hand, in heavy noble-gas atoms (Kr to Rn), the 2e-BP correction tended to overshoot energy lowering, and in a super-heavy atom (E118), evidences of collapse of the 2e-BP correction were observed. (C) 2007 Elsevier B.V. All rights reserved.

    DOI

  • SAC and SAC-CI calculations of excitation and circular dichroism spectra of straight-chain and cyclic dichalcogens

    Junji Seino, Yasushi Honda, Masahiko Hada, Hiroshi Nakatsuji

    JOURNAL OF PHYSICAL CHEMISTRY A   110 ( 33 ) 10053 - 10062  2006年08月  [査読有り]

     概要を見る

    Accurate quantum-chemical calculations of the excitation energies and the rotatory strengths of dichalcogens R-Ch-Ch-R(Ch) S, Se, Te) were carried out with the symmetry adapted cluster ( SAC) and SAC-configuration interaction (CI) methods. A series of straight-chain molecules ( dihydrogen dichalcogenide, dimethyl dichalcogenide, and (+)-bis(2-methylbutyl) dichalcogenide) and one cyclic molecule ( 2,3-(R,R)dichalcogenadecalin) were adopted for comparative analysis. The calculated excitation and circular dichroism ( CD) spectra were in good agreement with experimental ones (Laur, P. H. A. In Proceedings of the Third International Symposium on Organic Selenium and Tellurium Compounds; Cagniant, D., Kirsch, G., Eds.; Universite de Metz: Metz, 1979; pp 219-299) within 0.3 eV. The fitting CD spectra also reasonably reproduced the experimental ones. In all the molecules adopted, the first and second lowest bands were assigned to the n-sigma*(Ch-Ch) transition and the third and fourth lowest bands to the n-sigma*(Ch-R) transition. The first and second lowest bands apparently depended on the R-Ch-Ch-R dihedral angle, suggesting that the orbital energies of two sigma*(Ch-Ch) change with the R-Ch-Ch-R dihedral angle. This calculated trend agrees with two empirical rules: the C-2 rule and the quadrant rule.

    DOI

▼全件表示

Misc

  • 量子化学的記述子を用いた反応予測手法の開発と予測に寄与する記述子の解析

    藤波美起登, 清野淳司, 中井浩巳

    化学工業   70   31 - 37  2019年12月  [招待有り]

    記事・総説・解説・論説等(学術雑誌)  

  • 相対論的量子化学における理論・計算手法の基礎

    清野淳司

    フロンティア(理論化学会)   4   3 - 20  2019年10月  [招待有り]

    担当区分:筆頭著者, 責任著者

    記事・総説・解説・論説等(学術雑誌)  

  • 人工知能を用いた化学反応の予測と反応条件最適化

    藤波美起登, 清野淳司, 中井浩巳

    マテリアルズ・インフォマティクスによる材料開発と活用集(技術情報協会)、第8章     379 - 384  2019年01月  [招待有り]

    記事・総説・解説・論説等(商業誌、新聞、ウェブメディア)  

  • 理論化学とインフォマティクスの融合による反応設計

    藤波 美起登, 清野 淳司, 中井 浩巳

    化学と工業   71 ( 8 )  2018年08月  [招待有り]

  • インフォマティクスとの融合による理論化学研究

    清野 淳司, 中井 浩巳

    化学工業   69 ( 1 ) 53 - 58  2018年01月  [招待有り]

  • インフォマティクスとの融合による理論化学研究の推進

    清野 淳司, 中井 浩巳

    PETROTECH   40   353  2017年05月  [招待有り]

  • 人工知能を用いた化学反応の予測: 新材料開発のスピードアップに向けて

    藤波 美起登, 清野 淳司, 中井 浩巳

    Material Stage   17   70  2017年02月  [招待有り]

  • 局所ユニタリー変換を用いた効率的な2成分相対論的密度汎関数理論の開発

    大山拓郎, 速水雅生, 五十幡康弘, 清野淳司, 中井浩巳, 中井浩巳, 中井浩巳, 中井浩巳

    分子科学討論会講演プログラム&要旨(Web)   11th  2017年

    J-GLOBAL

  • インフォマティクスによる反応の設計と予測- コンピュータを用いた化学反応の予言を目指して

    藤波 美起登, 清野 淳司, 中井 浩巳

    化学   71   68  2016年11月  [招待有り]

  • 第一原理計算を用いた重原子同位体における核の体積効果の解明:相対論効果の影響

    根本 佳介, 阿部 穣里, 清野 淳司, 波田 雅彦

    日本地球化学会年会要旨集   60 ( 0 )  2013年

     概要を見る

    同位体分別平衡における原子核の体積効果は重原子系で顕著になり、地球化学や宇宙化学の分野で重要である。これまで4成分相対論法に基づく量子化学的手法を用いて、同位体分別係数における核体積項を見積もる研究が行なわれている。4成分法は相対論的に正確であるが計算コストが高く、数原子分子への適応に限られるため、精度を落とさずにより大きな分子が計算できる理論の選定が望まれる。本研究では、4成分法の近似的な相対論法として有力な、Douglas-Kroll (DK) 法に基づく2成分法の精度を検証した。そこでスピン-軌道効果や高次の相対論効果の影響について、4成分法との比較を行った。ウラン分子系において体積効果の計算には、高次のDK変換項とスピン-軌道効果は共に寄与が大きく無視できない。無限次DK法にスピン-軌道効果を適切に考慮した理論を用いることで4成分法とほぼ同精度になり、計算コストを大幅に削減できることを明らかにした。

    CiNii

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受賞

  • 優秀講演賞(学術)

    2016年03月   日本化学会  

    受賞者: 清野 淳司

  • 吉田賞(論文賞)

    2015年05月   日本コンピュータ化学会  

    受賞者: 清野 淳司

  • 優秀講演賞

    2010年09月   分子科学会  

    受賞者: 清野 淳司

  • 優秀ポスター賞

    2007年09月   日本化学会第1回関東支部大会  

    受賞者: 清野 淳司

共同研究・競争的資金等の研究課題

  • 精度保証を考慮したオンライン機械学習型軌道非依存密度汎関数理論の開発

    日本学術振興会  科学研究費助成事業 基盤研究 (C)

    研究期間:

    2021年
    -
    2023年
     

  • 量子化学と情報学との融合による次世代密度汎関数理論と均一系触媒における反応 予測システムの開発

    戦略的創造研究推進事業  個人型研究(さきがけ)研究領域「理論・実験・計算 科学とデータ科学が連携・融合した先進的マテリアルズインフォマティクスのための基盤技術の 構築」

    研究期間:

    2017年10月
    -
    2021年03月
     

    清野 淳司

  • 大規模相対論的量子化学計算手法の開発と新元素戦略への応用

    科学研究費補助金  特別研究員奨励費

    研究期間:

    2012年
    -
    2014年
     

    清野 淳司

  • 電子情報のみを記述できる大規模・高精度・汎用的相対論的量子化学理論の開発

    科学研究費助成事業(早稲田大学)  科学研究費助成事業(若手研究(B))

    研究期間:

    2011年
    -
     
     

    清野 淳司

  • 4成分Dirac-Coulomb方程式と厳密に等価な2成分相対論方程式の構築と重原子 化合物系の分子物性への応用

    笹川科学研究助成 

    研究期間:

    2008年
    -
     
     

    清野 淳司

講演・口頭発表等

  • 人工知能(AI)技術と電子状態情報を用いた化学反応予測および反応条件最適化

    清野 淳司  [招待有り]

    R&D支援センター講習会(2回目)  

    発表年月: 2020年01月

  • 相対論的量子化学における理論・計算手法の基礎

    清野 淳司  [招待有り]

    第9回量子化学スクール  

    発表年月: 2019年12月

  • Orbital-Free Density Functional Theory Calculation Combined with Semi-Local Machine-Learned Kinetic Energy Density Functional

    清野 淳司  [招待有り]

    The 2nd Global Forum on Advanced Materials and Technologies for Sustainable Development (GFMAT-2)  

    発表年月: 2019年07月

  • 人工知能(AI)技術と電子状態情報を用いた化学反応予測および反応条件最適化

    清野 淳司  [招待有り]

    R&D支援センター講習会  

    発表年月: 2019年01月

  • 相対論的量子化学における理論・計算手法の基礎

    清野 淳司  [招待有り]

    第8回量子化学スクール  

    発表年月: 2018年12月

  • 人工知能を用いた化学反応の予測と反応条件の最適化

    清野 淳司  [招待有り]

    技術情報協会・講習会 触媒開発における人工知能、計算科学の活用―新しい触媒の探索、設計の具体的手法-  

    発表年月: 2018年08月

  • 理論・計算・実験化学とインフォマティクスの融合研究

    清野 淳司  [招待有り]

    分子科学研究所・理論・計算分子科学領域セミナーシリーズ  

    発表年月: 2018年06月

  • 次世代相対論的量子化学プログラムRAQETの紹介と理論化学研究の情報学との融合

    清野 淳司  [招待有り]

    新化学技術振興協会 先端科学・材料技術部会・コンピュータケミストリ分科会 次世代CCWG講演会  

    発表年月: 2018年03月

  • RAQET: Large-Scale Two-Component Relativistic Quantum Chemistry Program Package

    清野 淳司  [招待有り]

    International Symposium “Theoretical Design of Materials with Innovative Functions Based on Element Strategy and Relativistic Electronic Theory”  

    発表年月: 2017年12月

  • 相対論的電子論

    清野 淳司  [招待有り]

    第56回 分子科学若手の会 夏の学校 第五分科会  

    発表年月: 2016年08月

  • Large-scale relativistic quantum-chemical theory

    清野 淳司  [招待有り]

    原子衝突学会第39回年会(第11回アジア原子分子物理国際シンポジウム (AISAMP11) 合同セッション)  

    発表年月: 2014年10月

  • Efficient Relativistic Quantum Theory and Its Analytical Energy Gradient Scheme for Large Molecule

    清野 淳司  [招待有り]

    XVIIIth International Workshop on Quantum Systems in Chemistry, Physics and Biology (QSCPXIII)  

    発表年月: 2013年12月

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特定課題研究

  • 任意の元素を含む大規模分子系のための分子理論の開発と希土類材料・触媒への応用

    2010年  

     概要を見る

     重原子を含む化合物の電子状態を定性的または定量的に計算するためには、相対論効果が不可欠である。この相対論効果の記述にはSchroedinger方程式では不十分であり、Dirac方程式を用いる必要がある。これまでDirac方程式を高精度に解くために様々な方法が提案されてきたが、未だ適用範囲は原子数個から構成される分子のみである。本研究では以下の二点の理論拡張により、大規模分子系が計算できる汎用的な相対論的量子化学理論の開発を行った。[1]相対論的な1電子ハミルトニアン生成の高速化、[2]相対論効果を正確に記述可能な一般化非制限Hartree-Fock(GUHF)法の、分割統治 (DC) 法への拡張。 まず[1]について説明する。Dirac方程式内のハミルトニアンであるDiracハミルトニアンは電子だけでなく陽電子の状態も記述するが、電子だけを扱う限り陽電子は不要である。そのためDiracハミルトニアンにユニタリー変換を施すことによって電子状態のみを記述するハミルトニアンを生成する様々な方法が提案されてきた。しかし、この変換は通常分子全体に対して行うため、計算時間はO(n3)(nは系の大きさ)であり、大規模系の計算に適さない。そこで本研究ではユニタリー変換の局所性を考慮した近似手法、「部分系におけるユニタリー変換手法」を開発した。この方法は各原子と各相互作用に分けた部分系について変換を行うことで高速化が実現される。本手法の計算コストはO(n1)であり、テスト計算を行ったほぼすべての分子系で近似による誤差は0.01 kcal/mol以内と、高精度かつ大規模系にも適用可能であることが確認された。 続いて[2]については、スピン-軌道相互作用などのαスピンとβスピンが混ざり合う相互作用を正確に記述できるGUHF法を、大規模分子理論であるDC法へと拡張し、プログラム作成を行った。本手法の分割による計算誤差を検証した結果、従来の制限HF法を基盤にしたDC法と同等の誤差を与えることが確認された。

 

現在担当している科目

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委員歴

  • 2021年10月
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    継続中

    理論化学会  幹事

  • 2020年
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    理論化学会  将来構想委員会 委員

  • 2016年
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    第19回理論化学討論会  実行委員

  • 2011年
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    ISTCP-VII  組織委員会事務局