Dynamical Property of Oriented Molecular Solution

采用Monte Calro方法模拟电极界面电解质溶液，用动力学密度泛函方法研究溶液分子电子态的随机变化引起的溶剂重取向，研究了具有取向的分子溶液的动力学行为.仿真研究的结果如下。电解质离子在电极表面形成吸附的层状结构，当外加电场时，其层状结构发生变形。该层被认为是前面所预期的亥姆霍兹双层。计算了电极反应速率的能隙依赖性（能隙定律）。它不是线性响应理论所期望的钟形响应，而是宽度较宽的梯形响应，表明在电极界面溶剂波动中有很强的非线性贡献。用动力学密度泛函方法进行分析的结果如下。在两种混合溶剂的取向动力学中观察到较大的非线性现象。明确了这种非线性的根源是两种溶剂分子的重取向运动与平移运动之间的耦合。结合这些结果，我们可以说取向分子溶液中存在较大的非线性现象。

Dynamical behavior of molecular solution with orientation was investigated by means of Monte Calro simulation of the electrolyte solution at the electrode interface and dynamical density functional method of reorientation of solvent due to a rarid change of electronic state of a solue molecule. The result of the simulation study is as follows. The adsorbed, layred structure of electrolyte ions is formed just in touch with the electrode surface and its layred structure is deformed when external field is applied. this layr is considered to be the Helmholtz double layr as expected before. The energy gap dependence of the electrode reaction rate (energy gap law) is calculated. It is not a bell shaped one which is expected by the linear response theory, but like trapezoid with broad width, suggesting a strong nonlinear contribution in the solvent fluctuation at the electrode interface. The result of the analysis by dynamical density functional method is as follows. A large nonlinear phenomenon was observed in the reorientational dynamics of the mixed solvents of two kinds. It was clearified that the origin of this nonlinearity is the coupling between the reorientational motion and the translational motion of the two kind of solvent molecules. Combinng those results, we can say that a large nonlinear phenomenon exists in the oriented molecular solutions.