Commutator Matrix in Phase Space Mapping Models for Nonadiabatic Quantum Dynamics

TL;DR

This paper introduces a new phase space mapping Hamiltonian for nonadiabatic quantum dynamics that uses a commutator matrix, improving accuracy over traditional methods in various systems.

Contribution

It presents a novel general mapping Hamiltonian with commutator variables, enhancing trajectory-based nonadiabatic dynamics simulations.

Findings

Better performance than Meyer-Miller Hamiltonian in benchmark tests

Applicable to both gas phase and condensed phase systems

Provides a more accurate approximation for nonadiabatic dynamics

Abstract

We show that a novel, general phase space mapping Hamiltonian for nonadiabatic systems, which is reminiscent of the renowned Meyer-Miller mapping Hamiltonian, involves a commutator variable matrix rather than the conventional zero-point-energy parameter. In the exact mapping formulation on constraint space for phase space approaches for nonadiabatic dynamics, the general mapping Hamiltonian with commutator variables can be employed to generate approximate trajectory-based dynamics. Various benchmark model tests, which range from gas phase to condensed phase systems, suggest that the overall performance of the general mapping Hamiltonian is better than that of the conventional Meyer-Miller Hamiltonian.