报告摘要：

 

Dynamics is crucial in many research fields, for instance, charge transport, electron relaxation, exciton diffusion, electron-hole separation, and singlet fission. While both purely quantum and purely classical methods cannot describe these processes properly, nonadiabatic molecular dynamics in a mixed quantum-calssical manner provides the most popular and reliable solution. Tully's fewest switches surface hopping (FSSH) is perhaps the most widely used strategy so far owing to its appealing simplicity, ease of implementation, and computational efficiency. At the meanwhile, however, various situations requiring improvements have been identified. FSSH lacks the capability of describing the superexchange mechanism of population transfer for systems with static disorders or many-particle transitions. In addition, FSSH encounters the so-called trivial, or unavoided, crossing problem when high density of states come into play. In this talk, I will discuss my recent developments in nonadiabatic molecular dynamics, including the global flux surface hopping and Liouville space surface hopping methods, which can well capture superexchange dynamics, as well as self-consistent surface hopping and flexible surface hopping methods, which describe trivial crossings accurately and efficiently. These techniques have been applied to investigate the mechanism of Auger relaxation in quantum dots, singlet fission in pentacene dimers, and charge transport in molecular crystals. The proposed methods are universal, efficient, and thus are sutable to describe various other dynamical processes in physics, chemistry, biology, and materials sciences.