Property prediction of charge transport for multi-halogen-substituted pyrene by density functional theory calculation

A series of reorganization energies of multi-halogen-substituted pyrenes were calculated by the density functional theory method [B3LYP/6-31++G(d,p)]. The reorganization energies decreased in the order of substituted halogen species, that is, fluorine, chlorine, and bromine. Among the bromine-substituted pyrenes, 1,3,6,8-tetrabromopyrene showed the lowest electron reorganization energy. Its charge transfer integrals were calculated on the basis of the known crystal structure and found to be larger in the stacking direction than those in the molecular plane direction. The estimated electron mobility in the stacking direction was 1.8 × 10−4 cm2 V−1 s−1. This value is about 20 times larger than that of previously reported hydroxypyrene.