Quantum chemical study of different substituents effect on the charge transport properties of hexabenzocoronene

In this paper, we used density functional theory (DFT) at the B3LYP/6-311+G(d), M06-2X/6-311+G(d) or CAM-B3LYP/6-311+G(d) level to compute the charge transport rates of twelve hexabenzocoronene molecules substituted with different substituents. The results show that the long-range correction functional CAM-B3LYP is more suitable for the study of the charge transport properties of the target system. Two hexabenzocoronene derivative molecules with six —CH₃ or —CN substituents have relatively large hole mobilities compared with the parent hexabenzocoronene, which are 2.51 cm²·V⁻¹·s⁻¹ and 0.92 cm²·V⁻¹·s⁻¹, respectively. They can be designed as a p-type organic semiconductor. Three hexabenzocoronene derivatives with six —SH, —CH₂SCH₃ or —COOCH₃ substituents have relatively small hole mobilities compared with the parent hexabenzocoronene. The electron mobility of five hexabenzocoronene derivatives with six —SCH₃, —OCH₃, —OH, —NHCH₃, —N(CH₃)₂ substituents is 1.7~18 times that of the hole mobility, and can be designed as n-type organic semiconductors.