title: State-dependent molecular dynamics.
abstract: This paper proposes a new mixed quantum mechanics (QM)-molecular mechanics (MM) approach, where MM is replaced by quantum Hamilton mechanics (QHM), which inherits the modeling capability of MM, while preserving the state-dependent nature of QM. QHM, a single mechanics playing the roles of QM and MM simultaneously, will be employed here to derive the three-dimensional quantum dynamics of diatomic molecules. The resulting state-dependent molecular dynamics including vibration, rotation and spin are shown to completely agree with the QM description and well match the experimental vibration-rotation spectrum. QHM can be incorporated into the framework of a mixed quantum-classical Bohmian method to enable a trajectory interpretation of orbital-spin interaction and spin entanglement in molecular dynamics.
authors.affiliation: Department of Aeronautics and Astronautics, National Cheng Kung University, Tainan 701, Taiwan. cdyang@mail.ncku.edu.tw.
authors.forename: Ciann-Dong
authors.initials: CD
authors.lastname: Yang
authors.affiliation: Department of Aeronautics and Astronautics, National Cheng Kung University, Tainan 701, Taiwan. principlex@yahoo.com.tw.
authors.forename: Hung-Jen
authors.initials: HJ
authors.lastname: Weng
mesh_terms: D008962:Models, Theoretical; D011789:Quantum Theory