Electronic and optical properties of silole-based derivatives

Purpose - The purpose of this paper is to focus on the development of highly efficient emission materials for light-emitting diodes (LEDs). Design/methodology/approach - The equilibrium geometries of silole-based derivatives are optimised by means of DFT/B3LYP method with the 6-31G(d) basis set in this paper. The geometries of single-excitation are optimised using the ab initio configuration interaction with single excitations/6-31G(d), the first singlet excited states and optical properties are calculated by using time-dependent density-functional theory based on the 6-31G(d) basis set. Findings - The highest occupied molecular orbital and lowest unoccupied molecular orbital suffer larger effects from the variation of the substituent groups of methyls and phenyls. The absorption wavelengths of all the cases are similar, but the emission wavelengths are significantly different. Research limitations/implications - Solid-state stacking effect is not included in this paper. Originality/value - In view of the application of silole-based derivatives systems, the control of photophysical properties and electronic structures by structural modification is relevant to further molecular design.