Time‐dependent wavepacket diffusion method and its applications in organic semiconductors

Abstract

Although the carriers in organic semiconductors commonly follow the hopping‐type motions caused by strong carrier‐phonon interactions, they can also present a band‐like behavior in well‐performed organic crystals. In this article, we review a unified model to describe the carrier dynamics covering from the hopping‐type to band‐like motions, the time‐dependent wavepacket diffusion method proposed in our group recently. In the method, the effects of vibrational motions of organic molecules and inter or intramolecular electronic couplings are considered as the fluctuations to the carrier dynamics. Numerical simulations demonstrate that the computational cost of present method is similar to that of mixed quantum‐classical methods, but it overcomes the deficiency in those methods that the detailed balance principle is not satisfied. We further present how to combine electronic structure calculations and molecular dynamics simulations with the present model to reveal the carrier dynamics in realistic organic semiconductors. © 2014 Wiley Periodicals, Inc.