3-(3′-吡啶基)-6-芳基-1，2，4-三唑并[3，4-b]-1，3，4-噻二唑衍生物基态和激发态性质

Properties at the Ground State and Excited State of 3-(3'-pyridyl)-6-aryl.1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole Derivatives

用密度泛函B3LYP方法对3-(3'-吡啶基)-6-芳基-1,2,4-三唑并[3,4-b]-1,3,4-噻二唑衍生物(芳基为苯基、3-吡啶基和苯乙烯基)进行基态几何构型全优化,计算分子的电离势I_p和电子亲和势E_A等相关能量,并用Zerner间略微分重叠(ZINDO)和含时密度泛函(TDDFT)方法计算吸收光谱,用单组态相互作用方法(CIS)优化三种化合物分子的S_1激发态结构,分析其能量与发射光谱的关系,计算溶剂中分子的吸收和发射光谱,并与实验结果对照.计算结果表明,从3-(3'-吡啶基)-6-苯基-1,2,4-三唑并[3,4-b]-1,3,4-噻二唑分子(化合物A)到3-(3'-吡啶基)-6-(3'-吡啶基)-1,2,4-三唑并[3,4-b]-1,3,4-噻二唑分子(化合物B)以及3-(3'-吡啶基)-6-对乙烯苯基-1,2,4-三唑并[3,4-b]- 1,3,4-噻二唑分子(化合物C)的电子亲和势依次增大,愈来愈容易接受电子,吸收光谱和发射光谱红移.

The ground states of 3-（3＇-pyddyl）-6-aryl-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole derivatives （in which, aryl is phenyl （compound A）, 3＇-pyridyl （compound B）, or styryl （compound C）） were optimized with density functional theory at B3LYP level. Ionization potential （Ip）, electron affinity （EA）, and other energies of the three compounds were calculated. Absorption spectra were obtained by using Zemer＇ s intermediate neglect of differential overlap （ZINDO） and time- depended density functional theory （TDDFT） methods. Single-excitation configuration interaction （CIS） method was used to calculate the S1 excited states of the three compounds and to analyze the relationship between their energies and emission spectra. The absorption and emission spectra were calculated in solvent and compared with the experimental data. The results indicated that the abilities for accepting electrons from A, B to C were strengthened for their electron affinities were increased in turn, and the absorption as well as emission spectra were red-shifted.