title: First-principles investigation of the electronic and conducting properties of oligothienoacenes and their derivatives.
abstract: Herein, we calculated reorganization energies, vertical ionization energies, electron affinities, and HOMO-LUMO gaps of fused thiophenes and their derivatives, and analyzed the influence of different substituents on their electronic properties. Furthermore, we simulated the angular resolution anisotropic mobility for both electron- and hole-transport, based on quantum-chemical calculations combined with the Marcus-Hush electron-transfer theory. We showed that: 1) styrene-group substitution can effectively elevate the HOMO energy level and lower the LUMO energy level, and therefore lower both the hole- and electron-injection barriers; and 2) chemical oxidation of the thiophene ring can significantly improve the semiconductor properties of the fused oligothiophenes through a decrease of the injection barrier and an increase in the charge-transfer mobility for electrons but without lowering their hole-transfer mobilities, which suggests that it may be a promising way to convert p-type semiconductors into ambipolar or n-type semiconductor materials.
authors.affiliation: State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P.R. China.
authors.forename: Jin-Dou
authors.initials: JD
authors.lastname: Huang
authors.forename: Shu-Hao
authors.initials: SH
authors.lastname: Wen
authors.forename: Ke-Li
authors.initials: KL
authors.lastname: Han