有机小分子空穴传输材料取代基效应的理论研究

Theoretical Study on the Substitute Effect of Organic Small Molecular Hole Transfer Materials

在B3LYP/6-31G(d)水平下对N,N′-二苯基-N,N′-二(1-萘基)-1,1′-联苯-4,4′-二胺(以下简称NTD)及其衍生物(以下简称NTDs)的中性态和离子态结构进行优化,得到各物质的重组能并进行比较。结果显示,NTD分子的化学修饰对重组能λ变化趋势的影响是电子诱导效应和共轭效应共同作用的结果:(1)吸电子诱导效应会引起NTD分子重组能的升高;多重取代位的吸电子效应对分子重组能影响具有相互抵消的作用,不具有简单加和性;给电子诱导效应会引起NTD分子重组能的降低;(2)o位、m位的正共轭效应使体系重组能剧烈升高,共轭作用在o位、m位取代时占主导作用;p位的正共轭效应使体系重组能降低;(3)大范围的共轭π键可能引起所取代的苯环电子分布发生根本性变化,导致分子构型随之发生剧烈变化,从而重组能急剧升高。

In this article,the geometry of all molecules,including N,N′-diphenyl-N,N′-bis(1-naphthyl)-(1,1′-biphenyl)-4,4′-diamine(NTD)and its derivatives(NTDs),is optimized for both the neutral and cation states.Then the reorganization energy is calculated.All calculations are performed at B3LYP/6-31G(d)level.The results indicate that the chemical modifications on NTD could induce the variety of the reorganization energy.And this can be attributed to the interaction of inductive effect and conjugated effect.(1)The electron-withdrawing effect will increase the reorganization energy.The reorganization energy will be reduced with the electron-donating effect.The electron absorption effect of multiple substitutions has a counteracting effect on molecular reorganization energy,which does not have simple additive property.(2)The ortho-,meta-positive conjugate effect will increase the reorganization energy dramatically,while the para-positive conjugate effect will reduce the reorganization energy.(3)A wide range of conjugatedπ-bonds might induce the fundamental changes in the electron distribution of the substituted benzene ring,resulting in dramatic changes in the molecular configuration,and the sharply rise of the reorganization energy.