Non-Condon效应对电子转移速率影响的理论模拟及其在有机半导体中的应用  

Theoretical investigation of the non-Condon effect on electron transfer:Application to organic semiconductor

作　　者：张伟伟[1] 赵仪[1] 梁万珍[2] 

机构地区：[1]固体表面物理化学国家重点实验室福建省理论与计算化学重点实验室厦门大学化学化工学院,厦门361005 [2]合肥微尺度物质科学国家实验室中国科学技术大学化学物理系,合肥230026

出　　处：《中国科学：化学》2011年第4期569-578,共10页SCIENTIA SINICA Chimica

基　　金：国家自然科学基金(20833004;21073146)的资助

摘　　要：随着Condon近似下各种电子转移理论的不断发展与完善和人们对non-Condon效应在电子转移过程中重要作用认识的逐步深入,已建立了几个理论模型来研究这种效应对电子转移速率的影响.本文主要总结了近两年来我们在non-Condon效应电子转移理论方面的工作,首先阐述了指数型、高斯型以及直线型non-Condon电子转移速率的全量子表达式,然后运用该理论模型以及分子动力学模拟计算了二噻吩四硫富瓦烯(DT-TTF)有机半导体的迁移率.此外,还进一步利用数值模拟详细研究了这三种线型的non-Condon效应在量子尺度上对电子转移速率的影响.The non-Condon effect plays an important role in the process of electron transfer（ET） .Several theoretical models have been proposed to investigate its effect on ET rates.In this paper,we overview a theoretical method for the calculations of the non-Condon ET rate constants proposed by us,and its applications to organic semiconductors.First,full quantum expressions of the non-Condon ET rates are presented with the electronic couplings having exponential,Gaussian and linear dependences in terms of the nuclear coordinates,respectively.The proposed formulas have closed forms in time domain and they thus can be easily applied to multi-mode systems.Then,the driving force dependence of the ET rates involving the non-Condon effect are calculated with use of full quantum mechanical formulas.It is found that these dependences show very different properties from the Marcus one.As an example of applications,the approaches are used to investigate the non-Condon effect on the mobility of the organic semiconductor dithiophene-tetrathiafulvalene（DT-TTF） .The results manifest that the non-Condon effect enhances ET rates compared with the Condon approximation,and static fluctuations of electronic coupling dominates the ET rate in the DT-TTF,which has been confirmed by the molecular dynamics simulation.

关 键 词：电子转移速率 Condon近似 non-Condon效应 迁移率 分子动力学模拟 

分 类 号：O469[理学—凝聚态物理]