Department of Chemistry, Chemical Physics Theory Group, University of Toronto, Toronto, ON M5S 3H6, Canada.
J Chem Phys. 2010 Aug 28;133(8):084502. doi: 10.1063/1.3475773.
Quantum-classical Liouville theory is used to simulate the dynamics of systems containing conical intersections. In particular quantum dynamical effects on the electronic population transfer and coherence in a quantum subsystem that arise from the presence of an environment are studied. The environment, in turn, is partitioned into an immediate environment representing, say, local molecular vibrations, and a bath representing other degrees of freedom. Population transfer may be enhanced or suppressed, depending on the relative values of the characteristic frequencies of the immediate environment and bath. Electronic decoherence and the destruction of geometric phase effects were observed for bath frequencies that are large relative to the molecular vibrations. The dynamics at higher dimensional conical intersections was found to be very sensitive to the environmental coupling. When a single collective solvent coordinate couples directly to the electronic subsystem, the characteristic frequency of the new coordinate, relative to that of the nuclear vibrational modes, has a strong effect on the population dynamics. The results also serve as a test of the QCL dynamical scheme for future applications to more detailed molecular descriptions of condensed phase environments for conical intersection dynamics.
量子经典刘维尔理论被用于模拟含有圆锥交叉的系统的动力学。特别是，研究了由于环境的存在而在量子子系统中产生的电子布居转移和相干的量子动力学效应。反过来，环境被划分为代表局部分子振动的直接环境和代表其他自由度的浴。根据直接环境和浴的特征频率的相对值，布居转移可能会增强或抑制。对于相对于分子振动较大的浴频率，观察到电子退相干和几何相位效应的破坏。发现更高维圆锥交叉处的动力学对环境耦合非常敏感。当单个集体溶剂坐标直接耦合到电子子系统时，相对于核振动模式的新坐标的特征频率对布居动力学有很强的影响。这些结果也为未来在凝聚相环境中更详细的分子描述中应用 QCL 动力学方案对圆锥交叉动力学进行测试。
