Journal of Computer Chemistry, Japan

[Published online Journal of Computer Chemistry, Japan Vol.15, 217-218, by J-STAGE]
<Title:> 分子動力学法を用いた4-n-alkyl-4′-cyanobiphenyl (nCB) の熱伝導率シミュレーション
<Author(s):> 高橋　祐貴, 石川　良, 大木　竜勝, 川内　進
<Corresponding author E-Mill:> skawauch(at)polymer.titech.ac.jp
<Abstract:> Thermal conductivity of 4-n-alkyl-4′-cyanobiphenyl (nCB) simulated by using molecular dynamics method. We modified the dihedral angle parameter and the LJ parameters of the original AMBER Force Field for nCB. The dihedral angle parameter was corrected by using quantum chemical calculation, and the LJ parameters were fitted to reproduce the experimental data. Thermal conductivity was calculated by Green-Kubo Method. MD calculation using the corrected force field gave good thermal conductivity close to experimental value and successfully reproduced the anisotropy of thermal conductivity in the liquid crystal phase.
<Keywords:> Thermal conductivity, Molecular Dynamics, Corrected force field, Anisotropy of thermal conductivity, Green-Kubo Method
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/6/15_2016-0054/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, 215-216, by J-STAGE]
<Title:> Ru(0)触媒による共役ジエンとヘテロ環状化合物のクロスカップリング反応機構の理論的解明
<Author(s):> 出口　光, 西久保　椋, 大槻　恒太, 駒崎　弘樹, 川内　進
<Corresponding author E-Mill:> skawauch(at)polymer.titech.ac.jp
<Abstract:> Mechanistic studies for linear cross-dimerization between 2,3-dimethylbuta-1,3-diene and 2,5-dihydrofuran by a Ru(0) complex, Ru(η⁶-naphthalene) (η⁴ 1,5-COD), were performed computationally. The rate-determining steps of main and side reactions are different mechanisms, and correspond to the reductive elimination step and the oxidative coupling step, respectively. This suggests that the yield of the main product may be improved by modification of the heterocyclic compound or catalyst structure. In addition, the computational studies predicted that cross-dimerization between 2,3-dimethylbuta-1,3-diene and 2,5-dihydropyrrole may occur via a similar reaction mechanism.
<Keywords:> oxidative coupling, reductive elimination, cross-dimerization, Ru(0) complex, DFT calculations
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/6/15_2016-0055/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, 213-214, by J-STAGE]
<Title:> [M(ABC)₆]錯体の配座解析
<Author(s):> 山　博史, 安孫子　誉晃, 伊藤　美咲, 脇　克志, 　了爾, 御厨　正博
<Corresponding author E-Mill:> saki(at)sci.kj.yamagata-u.ac.jp
<Abstract:> Enumeration of the conformers and conformational analysis were successfully conducted for an octahedral [M(ABC)₆] complex. In this report the methods and results were briefly described. In the enumeration, 7173 conformers were found by the computational group theory method, and among them, 130 conformers were found to have stable M(AB)₆ cores of S₆ symmetry. The structures of the 130 conformers of [Zn(DMSO)₆]²⁺ (DMSO: dimethylsulfoxide) were optimized by the DFT method, and the most stable conformer was obtained.
<Keywords:> 配座解析, 配座異性体, 数え上げ, 正八面体型錯体, 密度汎関数法
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/6/15_2016-0067/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, 211-212, by J-STAGE]
<Title:> ケイ酸塩鉱物の電子状態及びXANES計算
<Author(s):> 高橋　修, 末永　太河
<Corresponding author E-Mill:> shu(at)hiroshima-u.ac.jp
<Abstract:> We estimated surface energies of all flat surfaces of forsterite within the framework of density functional theory. We found that surface energy of (120) surface is the lowest and those of (010), (130) and (112) surfaces are followed subsequently. Morphology of forsterite at 0 K is predicted. Calculated Si K-edge XANES spectra of silicon in forsterite are consistent with experiments.
<Keywords:> Soft X-ray absorption spectroscopy, silicate compounds, surface energy, DFT
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/6/15_2016-0058/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, A55-A55, by J-STAGE]
<Title:> 2016年秋季年会を終えて，・・異次元の世界で!
<Author(s):> 半田　真
<Abstract:>
<Keywords:>
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/6/15_foreword_15_6/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, A51-A51, by J-STAGE]
<Title:> 特集「量子水素の科学」に寄せて
<Author(s):> 立川　仁典
<Abstract:>
<Keywords:>
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/5/15_foreword_15_5/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, 119-123, by J-STAGE]
<Title:> ミュオニウム化学反応の新展開
<Author(s):> 高柳　敏幸, 吉田　崇彦
<Corresponding author E-Mill:> tako(at)mail.saitama-u.ac.jp
<Abstract:> 正または負電荷を有するミューオン粒子を用いて，ミュオニウム(0.114 amu) およびミュオニックヘリウム(4.11 amu)と呼ばれる水素原子の同位体をつくりだすことができる．これを利用することによって，H/D/Tを超えた質量比の同位体効果を観測することができ る．ミュオニウムはその小さな質量のため，化学反応系の水素原子がミュオニウムに置換されると，ゼロ点振動エネルギーやトンネル効果による大きな 量子効果を示す．また，反応経路そのものが変化する例や，遷移状態が安定化する特異な現象も存在する．
<Keywords:> Muon, Muonium, Muonic helium, Isotope effect, Nuclear quantum effect, Vibrational bonding
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/5/15_2016-0006/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, 148-154, by J-STAGE]
<Title:> 核・電子軌道法における原子核軌道エネルギーとプロトン束縛エネルギー計算
<Author(s):> 五十幡　康弘, 中井　浩巳
<Corresponding author E-Mill:> nakai(at)waseda.jp
<Abstract:> 核・電子軌道 (NOMO) 法は，原子核に対して軌道の概念を導入した量子化学理論である．NOMO法におけるHartree-Fock (HF)方程式の解として得られる原子核軌道エネルギーは，全エネルギーや軌道そのものと比較して注目されていない．本論文では，NOMO法における原子 核軌道エネルギーの物理的意味とpost-HF理論への応用を述べる．特に，最近開発されたプロトンプロパゲーター法による束縛エネルギーの見積 りについて，計算例を含めて紹介する．
<Keywords:> Nuclear orbital plus molecular orbital method, Nuclear orbital energy, Proton propagator method, Proton binding energy, Divide-and-conquer method
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/5/15_2016-0011/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, 192-198, by J-STAGE]
<Title:> Ionic Hydrogen Bonding Vibration in OH^–(H₂O)_2-4
<Author(s):> Masato MORITA, Kaito TAKAHASHI
<Corresponding author E-Mill:> kt(at)gate.sinica.edu.tw
<Abstract:> Focusing on the OH^–(H₂O)_{2 4} clusters, we have theoretically studied the strongly red shifted ionic hydrogen bond (IHB) OH stretching vibration of water molecules directly bound to the hydroxide. Our calculations show that a systematic blue shift of the IHB OH peak is observed with the increase in the number of water molecules in the first solvation shell. Furthermore, we showed that the vibrational signature of the four coordinated hydroxide for OH^–(H₂O)₄ will be observed in the 2800 3200 cm^-1 range.
<Keywords:> Anharmonic proton vibration, Hydroxide water cluster, Hydrogen bonding, Anion hydration, Quantum chemistry
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/5/15_2016-0012/_article/-char/ja/

[Published online Journal of Computer Chemistry, Japan Vol.15, 170-176, by J-STAGE]
<Title:> 固体表面に存在する水素原子が示す量子効果
<Author(s):> 奥山　弘
<Abstract:> Quantum effect is manifest for hydrogen atoms on surfaces as well as for those in solution and solids. The excited states of a hydrogen atom directly adsorbed on metal surfaces are beyond the diffusion barrier, thus being delocalized to the next sites, and even spread over the entire surface in the low-coverage limit. In addition, water and hydroxyl group on the surfaces show significant quantum effect, due to tunneling and zero-point motion of the hydrogen atom. We briefly review some experimental and theoretical studies that revealed the quantum effect of the hydrogen atom on the surfaces.
<Keywords:> Hydrogen atom, Metal surface, Quantum delocalization
<URL:> https://www.jstage.jst.go.jp/article/jccj/15/5/15_2016-0013/_article/-char/ja/