月別: 2021年3月

[Published online Journal of Computer Chemistry, Japan Vol.19, 128-130, by J-STAGE]
<Title:> Implementation of Picture Change Corrected Density Functional Theory Based on Infinite-Order Two-Component Method to GAMESS Program
<Author(s):> Chinami TAKASHIMA, Junji SEINO, Hiromi NAKAI
<Corresponding author E-Mill:> nakai(at)waseda.jp
<Abstract:> We implemented the picture change correction method for two-electron Coulomb interaction and density operator, 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.
<Keywords:> Relativistic effect, Infinite-order two-component theory, Local unitary transformation, Picture change, DFT
<URL:> https://www.jstage.jst.go.jp/article/jccj/19/4/19_2021-0002/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.19, 125-127, by J-STAGE]
<Title:> 環状ペプチドの膜透過における溶媒和自由エネルギー計算
<Author(s):> 栁　昂輝, 原田　隆平, 満田　祐樹, 重田　育照
<Corresponding author E-Mill:> shigeta(at)ccs.tsukuba.ac.jp
<Abstract:> The solvation free energies of cyclic dipeptides (CDPs) for a membrane were calculated to evaluate their membrane permeabilities. As a result, there were energy barriers between the membrane center and interface for each CDP. Furthermore, the profiles of solvation free energy depended on the amino acids that construct each CDP. These results indicate that each CDP changes its membrane permeability. Our results will be useful for designing cyclic peptides in the field of medium-molecular-weight drugs.
<Keywords:> MD, Cyclic Dipeptide (CDP), Solvation Free Energy, Energy Representation, Membrane Permeation Process
<URL:> https://www.jstage.jst.go.jp/article/jccj/19/4/19_2021-0008/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.19, 131-132, by J-STAGE]
<Title:> プロトン伝導性PVPA-xIm複合体のプロトン伝導機構の理論的解明
<Author(s):> 堀　太, 末武　鋭也, 井田　朋智, 水野　元博, 重田　育照
<Corresponding author E-Mill:> hori(at)ccs.tsukuba.ac.jp
<Abstract:> This paper overviews the local structures and dynamics of imidazole (Im) in proton-conducting poly (vinylphosphonic acid)-Im (PVPA-xIm) composites investigated by density functional theory calculations and molecular dynamics simulations. These calculations propose the proton conduction mechanism of PVPA-xIm based on Grotthuss-type mechanism consisting the following processes: proton transfers from PVPA to Im and between Im, and the reorientation of Im in the hydrogen-bond Im cluster.
<Keywords:> Imidazole, Proton conduction mechanism, Molecular dynamics simulation, Density functional theory, Grotthuss-type mechanism
<URL:> https://www.jstage.jst.go.jp/article/jccj/19/4/19_2020-0028/_article/-char/ja/