Design of fused bithiophene systems containing silole and five-membered heterocycles for optoelectronic materials

Abstract

The influence of various substituents of six fused-ring systems designed on the basis of the bithiophene moiety on the geometric and electronic structures, their injection, transport and optical properties, was investigated using quantum chemical computations with the DFT and TD-DFT methods, and the wavefunction CASPT2 method. Compared to the parent compounds, most of modified molecules with substituents at α-position of fused-ring bithiophene get smaller band gaps and are better in the electron injection and transport properties.