苯乙烯桥联的三苯烯的电子结构和荧光光谱

以苯乙烯桥联的三苯烯分子为模型化合物, 自行设计一系列分子, 用半经验AM1方法和密度泛函理论在B3LYP/3-21G水平上对其进行结构优化. 在B3LYP/3-21G优化构型基础上, 用INDO/CIS和B3LYP/3-21G方法计算其电子吸收光谱和碳原子化学位移. 结果表明, 母体化合物中取代基的数目、供电子能力和立体效应将影响其LUMO-HOMO(最低空轨道-最高占据轨道)能隙、空穴注入性能及热稳定性. —CN和—OH的存在将使化合物电子吸收光谱的第一吸收峰及主要吸收峰与母体相比发生红移. —CN上的C原子受N原子影响化学位移出现在低场, 与—CN相连的C原子由于具有较大的电子云密度化学位移向高场移动, 骨架上的C原子化学位移基本保持不变.

Electronic Structures and Fluorescent Spectra of 1,4-divinylphenyl-bridged Triphenylenes

A series of derivatives were designed based on the model compound 1,4-divinyphenyl-bridged triphenylene, and the structures were studied using the AM1 method and density functional theory (DFT) at the B3LYP/3-21G level. On the basis of the B3LYP/3-21G optimized geometries, the electronic spectra and 13C NMR spectra of the derivatives were calculated using the INDO/CIS and B3LYP/3-21G methods, respectively. The energy gaps, abilities of accepting holes, and thermal stabilities were affected by the number and electron-donating capability as well as steric effect of the substituents. The red shifts of the first and main absorptions in the electronic spectra of the derivatives relative to those of the parent compound were predicted in the presence of the groups -CN and -OH. The chemical shift of the carbon atom on -CN was transferred to the low field under the effect of the nitrogen atom. The chemical shifts of the carbon atoms associated with -CN were transformed into the high field owing to the high electron density. The chemical shifts of the carbon atoms on the conjugation skeleton were almost unchanged.