Potentiai Energy Surfaces and Dynamics of Chemical Reactions in Solution

溶液中化学反应的势能面和动力学

• 批准号: 10206205
• 负责人: KATO Shigeki
• 金额: $ 25.41万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research on Priority Areas (B)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10206205/
• 关键词: Potential Surface; Chemical Reaction; Dynamics; Reaction Path; Hamiltonian; Charge Polarization; Vibrationa Spectra; Water; 電子状態; 分子動力学; 液体統計力学; 溶媒効果

We have developed a method to construct a reaction path Hamiltonian for chemical reactions in solution based on the reference interaction site self-consistent field (RISM-SCF) electronic structure calculations of reacting solute molecule combined with molecular dynamic (MD) simulation calculations for bulk solvent. We applied this method to the S_N2 reaction CH_3Cl + Cl^- and the Menshutkin type reactions NH_3+CH_3X (X=Cl, Br, I) and examined the effect of solvent dynamics on the reaction rates. The transmission coefficient for the former was 0.71, which was consistent with the previous simulation calculations. We have also investigated the electronic polarization effect on the dynamics of molecules in solution with the use of charge response kernel (CRK) model, which was proposed previously by us. Three and frve site CRK models for water molecule were developed and the infrared and Raman spectra for bulk water were calculated. The five site model was shown to well reproduce the experimental spectral features. The present five site model was further applied to calculate the infrared spectrum of N-Methylacetamide (NMA) in aqueous solution. Finally, we proposed a new method to define the CRK which avoid the ambiguity in determining the effective charges at atomic sites.

基于反应溶质分子的参考相互作用位点自洽场（RISM-SCF）电子结构计算结合本体溶剂的分子动力学（MD）模拟计算，我们开发了一种构建溶液中化学反应哈密顿量的反应路径的方法。我们将此方法应用于 S_N2 反应 CH_3Cl + Cl^- 和 Menshutkin 型反应 NH_3+CH_3X (X=Cl, Br, I) 并研究了溶剂动力学对反应速率的影响。前者的传输系数为0.71，与之前的仿真计算结果一致。我们还利用我们之前提出的电荷响应核（CRK）模型研究了电子极化对溶液中分子动力学的影响。开发了水分子的三位点和五位点CRK模型，并计算了大量水的红外和拉曼光谱。五位点模型被证明可以很好地再现实验光谱特征。进一步应用五位点模型计算水溶液中 N-甲基乙酰胺 (NMA) 的红外光谱。最后，我们提出了一种定义 CRK 的新方法，避免了确定原子位点有效电荷时的模糊性。

项目成果

森田明弘: "An ab initio Analysis of Medium Perturbation on Molecular Polarizabilities"J. Chem. Phys.. 110. 11987 (1999)

Akihiro Morita：“分子极化率的介质扰动从头开始分析”J. Chem. 110. 11987 (1999)

K.Ohmiya: "RISM-SCF Study for the Rate Constant of SN2 Reaction CH3Cl+Cl- in Aqueous Solution"Chemical Physics Letter. 348. 75-81 (2001)

K.Ohmiya：“RISM-SCF 研究 SN2 反应 CH3Cl Cl- 在水溶液中的速率常数”化学物理快报。

H.Sakurai: "Theoretical Study of the Metal Oxidation Reaction Ti+O2→TiO+O:Ab Initio Calculation of the Potential Energy Surface and Classical Trajectory Analysis"Journal of Physical Chemistry A. (印刷中). (2002)

H. Sakurai：“金属氧化反应Ti+O2→TiO+O的理论研究：势能面的从头计算和经典轨迹分析”《物理化学杂志A》（出版中）。

H.Nakamura: "State Resolved Reaction Rates of the Spin-forbidden Predissociation of N2O : A Quantum Dynamic Study of the Rotational Effect"Journal of Chemical Physics. 112. 1785-1796 (2000)

H.Nakamura：“N2O 自旋禁阻预解离的状态解析反应速率：旋转效应的量子动力学研究”化学物理杂志。

S. Iuchi, A. Morita and S. Kato: "Molecular Dynamics Simulation with the Charge Response Kemel : Vibrational Spectra of Liquid Water and N-Methylacetamide in Aqueous Solution"J. Phys. Chem.. (in press). (2002)

S. Iuchi、A. Morita 和 S. Kato：“利用电荷响应 Kemel 进行分子动力学模拟：水溶液中液态水和 N-甲基乙酰胺的振动光谱”J。