强电场下化学反应体系非线性介电行为研究

Nonlinear dielectric behavior study of chemical reactions in a strong electric field

在强电场的作用下,化学反应体系的反应速率会发生改变,进而影响反应体系的平衡状态,然而其机理仍不清楚.本文从反应体系的介电特性出发,研究了强静电场与反应体系的相互作用.在只考虑二阶非线性响应时,对改进型的Smoluchowski方程进行勒让德多项式展开,推导出反应体系极化强度的一般表达式.同时利用异构反应讨论了具体的非线性变化,结果表明,极化过程中的二阶非线性项与极化强度之比与电场强度成正比,同时讨论并给出了该结果的适用范围.

In the presence of a strong electric field, novel phenomena always happen in chemical reactions, including the change of chemical reaction rate and the shifting of chemical equilibria. However, the mechanism is still unknown. This paper studies the interactions between chemical reaction systems and strong steady electric fields. Based on the theory of molecule reorientation, the modified Smoluchowski equation is expanded by the Legendre polynomials. The general expression of polarization is derived by considering the second-order nonlinear response. The nonlinear variation is also discussed through a simple isomerization reaction. The result shows that the ratio between the second-order nonlinear term and the polarization is proportional to the electric field. Meanwhile, the condition for which the result applies is also discussed.