He Xin, Liu Jian
Beijing National Laboratory for Molecular Sciences, Institute of Theoretical and Computational Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China.
J Chem Phys. 2019 Jul 14;151(2):024105. doi: 10.1063/1.5108736.
Based on the recently developed unified theoretical framework [J. Liu, J. Chem. Phys. 145(20), 204105 (2016)], we propose a new perspective for studying nonadiabatic dynamics with classical mapping models (CMMs) of the coupled multistate Hamiltonian onto the Cartesian phase space. CMMs treat the underlying electronic state degrees of freedom classically with a simple physical population constraint while employing the linearized semiclassical initial value representation to describe the nuclear degrees of freedom. We have tested various benchmark condensed phase models where numerically exact results are available, which range from finite temperature to more challenging zero temperature, from adiabatic to nonadiabatic domains, and from weak to strong system-bath coupling regions. CMMs demonstrate overall reasonably accurate dynamics behaviors in comparison to exact results even in the asymptotic long time limit for various spin-boson models and site-exciton models. Further investigation of the strategy used in CMMs may lead to practically useful approaches to study nonadiabatic processes in realistic molecular systems in the condensed phase.
基于最近发展的统一理论框架[J. Liu, J. Chem. Phys. 145(20), 204105 (2016)]，我们提出了一种新的视角，用于利用耦合多态哈密顿量在笛卡尔相空间上的经典映射模型（CMMs）来研究非绝热动力学。CMMs在经典地处理潜在电子态自由度时采用简单的物理布居约束，同时使用线性化半经典初值表示来描述核自由度。我们已经测试了各种基准凝聚相模型，这些模型有数值精确结果，范围从有限温度到更具挑战性的零温度，从绝热到非绝热区域，以及从弱到强的系统 - 浴耦合区域。与精确结果相比，即使在各种自旋 - 玻色子模型和位点 - 激子模型的渐近长时间极限下，CMMs也展示出总体上相当准确的动力学行为。对CMMs中使用的策略的进一步研究可能会导致在凝聚相中实际分子系统中研究非绝热过程的实用方法。
