【摘要】 用密度泛函理论(DFT)方法研究了基于苯并噻二唑和硅芴的一系列聚合物的基态和激发态结构、传输和荧光性质.聚合物的能隙、电离能、电子亲和势、最低激发能以及吸收光谱通过外推法得到.结果表明空穴、电子注入和传输性质受苯并噻唑在硅芴上的位置以及正丁基在噻吩上的位置影响很大.(SiF2-DHTBT1-m)n和(SiF1-DHTBT1-m)n(SiF和DHTBT分别代表硅芴和4,7-二(2-噻吩基)-2,1,3-苯并噻二唑)表现出较好的空穴和电子注入性质,而(SiF1-DHTBT1-o)n和(SiF1-DHTBT1-p)n的电荷注入性质较差.除(SiF1-DHTBT1-o)n外,聚合物的荧光光谱处于红光范围.更多还原

【Abstract】 The ground and excited states, charge- transport, and fluorescence properties of a series of polymers based on benzothiadiazole and silafluorene were investigated using density functional theory(DFT). The band gaps, ionization potentials, electron affinities, the lowest excitation energies, and absorption spectra of the polymers were estimated by extrapolating those of the oligomers to infinite chain lengths. The results show that the hole/electron injection/transport abilities and the optical properties of the polymers are significantly affected by the position of the benzothiadiazole group on the silafluorene group and the position of the butyl group on the thiophene group.(SiF2- DHTBT1- m)nand(SiF1- DHTBT1- m)n [hereafter SiF and DHTBT are silafluorene and 4,7-di(2-thienyl)-2,1,3-benzothiadiazole, respectively] show good hole and electron injection performances but(SiF1-DHTBT1-o)nand(SiF1-DHTBT1-p)nexhibit poor carrier injection performances. The predicted emission spectra of the polymers are located in the red visible-light range, except in the case of(SiF1-DHTBT1-o)n.更多还原