某些电荷转移反应中线性反应坐标确定的反应途径的非唯一性

在电子转移半经典模型的基础上,对氟代苯并菲组成的盘状液晶体系的电荷转移反应进行了研究,其反应动力学参数在量子化学B3LYP/6-31G(d,p)水平进行计算.研究中发现在反应物和产物的构型确定后,用线性反应坐标构造的反应途径和过渡态的构型不是唯一的.其原因是反应物和产物确定后,其独立内坐标的选择并不是唯一的.因此在计算电荷转移速率常数时必须考虑到多个过渡态构型才能得到定性正确的结果.

More than One Reaction Pathway Determined by Linear Reaction Coordinate in Some Charge Transfer Reactions

Based on the semiclassical model of the charge transfer, kinetic parameters of the charge transfer reaction at the molecular scale in discotic liquid crystal made of fluoro-triphenylene have been studied at a quantum chemical B3LYP/6-31G(d,p) level. It has been found that there are more than one reaction pathway and more than one transition state determined by linear reaction coordinate between one reactant and one product. The reason is that the independent internal coordinates of reactant and product could be chosen with different ways, even though the geometries of reactant and product have been determined. In order to get correct mobility of the charge carriers, the problem presented here has to be taken into account.