4,7-二(2-溴代噻吩-5-基)-2,1,3-苯并噻二唑-N-(1-辛基壬烷基)咔唑在ZnS(100)表面吸附的理论研究

采用密度泛函理论中的广义梯度近似(DFT/GGA)方法,在PW91/DNP水平上研究了4,7-二(2-溴代噻吩-5-基)-2,1,3-苯并噻二唑-N-(1-辛基壬烷基)咔唑(简称PC-DTBT)的低聚合物(PC-DTBT)n(n=1-5)的稳定性和化学活性.结果表明:随着聚合度增加,(PC-DTBT)n的稳定性降低,化学活性增强.采用密度泛函理论与周期性平板模型相结合的方法,研究了PC-DTBT单体在ZnS(100)表面的吸附,通过吸附前后化合物PC-DTBT的Mulliken charge和前线轨道分析表明:当PC-DTBT吸附在ZnS(100)表面时,ZnS(100)表面向PC-DTBT转移0.200 e电荷,前线轨道能隙变窄.理论预测的结果与实验值吻合.

Theory Study of 4,7-di(2-bromothien-5-yl)-2,1,3-benzothiazole-

The stability and chemical activity of the low polymer (PC-DTBT)n(n=1-5) for 4,7-di(2-bromothien-5-yl)-2,1,3-benzothiazole-N-(1-octylnonanyl)carbazole (PC-DTBT for short) are investigated by density functional theory(DFT) at the GGA/PW91/DNP level. The computational results show that the stability gradually decreased and the chemical activity gradually strengthened with the increasing of the polymerization degree. Moreover, the density functional theory and periodic slab model are used to investigate the monomer PC-DTBT adsorption on ZnS(100) surface. The Mulliken charge and frontier orbital of the ZnS(100)-PC-DTBT are also discussed. The results reveal that the charge of 0.200 e transfers from the ZnS(100) surface to the PC-DTBT and the energy gap becomes narrow during the adsorption has occurred. It is found that the above-mentioned theoretical calculations agree well with the experiment results.