基于苯并二噻吩和齐聚噻吩衍生物的光电性质理论研究

Theoretical study on the electronic and optical-properties of the Benzo[1,2,-b:4,5-b′e]dithiophene and oligothiophene derivatives

设计研究了以苯并二噻吩、齐聚噻吩为构筑单元,利用构筑单元间不同的连接方式构造的9个模型化合物,在pbe0/6-31G(d)水平上进行结构优化并计算分子的前线轨道、电离能、电子亲和势和重组能.利用重组能分析了设计分子的载流子传输能力.在TD-DFT水平上模拟了设计分子的吸收光谱.研究结果表明,设计分子光谱及传输性能与构筑单元间的连接方式紧密相关.当最长的齐聚噻吩连接在并噻吩上时具有最小的HOMO-LUMO能隙,最大吸收波长最长,且吸收强度大,是好的双极性传输材料.

Nine compounds were designed based on Benzo[1,2,-b：4,5-b′e]dithiophene（abbreviated as BDT） and oligothiophene as building blocks theoretically.Electronic and opticalproperties were comparatively studied by using DFT/PBE1PBE/6-31G（d） based on the optimized geometries at the same level.Calculated results suggest that the fram of BDT with the longest oligothiophene chain substituted on the fused thiophene ring possesses the lowest Eg and Largest maxima absorption wavelength with the strongest oscillator strength.In addition,low reorganization energy values of the hole and electron for b and c series of designed derivatives within the framework of the charge hopping model suggest that them to be good bipolar materials.