Antoniou Dimitri, Gelman David, Schwartz Steven D
Department of Biophysics, Albert Einstein College of Medicine, New York 10461, USA.
J Chem Phys. 2007 May 14;126(18):184107. doi: 10.1063/1.2731779.
The authors developed a new method for calculating the quantum evolution of multidimensional systems, for cases in which the system can be assumed to consist of a quantum subsystem and a bath subsystem of heavier atoms. The method combines two ideas: starting from a simple frozen Gaussian description of the bath subsystem, then calculate quantum corrections to the propagation of the quantum subsystem. This follows from recent work by one of them, showing how one can calculate corrections to approximate evolution schemes, even when the Hamiltonian that corresponds to these approximate schemes is unknown. Then, they take the limit in which the width of the frozen Gaussians approaches zero, which makes the corrections to the evolution of the quantum subsystem depend only on classical bath coordinates. The test calculations they present use low-dimensional systems, in which comparison to exact quantum dynamics is feasible.
作者们开发了一种新方法，用于计算多维系统的量子演化，适用于可假定系统由一个量子子系统和一个较重原子的浴子系统组成的情况。该方法结合了两个思路：首先从浴子系统的简单冻结高斯描述出发，然后计算对量子子系统传播的量子修正。这源于他们其中一人最近的工作，该工作展示了即使对应于这些近似演化方案的哈密顿量未知，也能计算对近似演化方案的修正。接着，他们取冻结高斯宽度趋近于零的极限，这使得对量子子系统演化的修正仅取决于经典浴坐标。他们给出的测试计算使用了低维系统，在其中与精确量子动力学进行比较是可行的。
