Wyatt Robert E, Babyuk Dmytro
Department of Chemistry and Biochemistry, Institute for Theoretical Chemistry, The University of Texas, Austin, Texas 78712, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2006 Apr;73(4 Pt 2):046701. doi: 10.1103/PhysRevE.73.046701. Epub 2006 Apr 10.
Ensembles of quantum trajectories are evolved to study time-dependent reaction dynamics in multidimensional systems with up to 25 vibrational modes. The equations of motion are formulated in curvilinear reaction path coordinates and all coupling terms are retained, including those involving curvature of the reaction path. The model potential is a Gaussian barrier along the translational coordinate coupled to M vibrational modes. Spatial derivatives needed to propagate the trajectories are evaluated by least squares fitting in a contracted basis set. Stable propagation of the trajectory ensembles was carried out until complete bifurcation into reflected and reactive subensembles. The reaction probabilities were evaluated by Monte Carlo integration of the multidimensional smooth transmitted densities. Computational results, including trajectory plots and time-dependent reaction probabilities, are presented for M = 1, 5, and 25 vibrational modes.
通过演化量子轨迹系综来研究具有多达25个振动模式的多维系统中的含时反应动力学。运动方程在曲线反应路径坐标中制定，所有耦合项都被保留，包括那些涉及反应路径曲率的项。模型势是沿着与M个振动模式耦合的平移坐标的高斯势垒。通过在收缩基组中进行最小二乘拟合来评估传播轨迹所需的空间导数。对轨迹系综进行稳定传播，直到完全分叉为反射子系综和反应性子系综。通过对多维平滑透射密度进行蒙特卡罗积分来评估反应概率。给出了M = 1、5和25个振动模式的计算结果，包括轨迹图和含时反应概率。
