State key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, Dalian 116023, PR China.
J Phys Chem A. 2013 Feb 21;117(7):1406-12. doi: 10.1021/jp312084r. Epub 2013 Feb 5.
A time-dependent quantum wave packet method is used to investigate the dynamics of the He + HeH(+)(X(1)Σ(+)) reaction based on a new potential energy surface [Liang et al., J. Chem. Phys.2012, 136, 094307]. The coupled channel (CC) and centrifugal-sudden (CS) reaction probabilities as well as the total integral cross sections are calculated. A comparison of the results with and without Coriolis coupling revealed that the number of K states N(K) (K is the projection of the total angular momentum J on the body-fixed z axis) significantly influences the reaction threshold. The effective potential energy profiles of each N(K) for the He + HeH(+) reaction in a collinear geometry indicate that the barrier height gradually decreased with increased N(K). The calculated time evolution of CC and CS probability density distribution over the collision energy of 0.27-0.36 eV at total angular momentum J = 50 clearly suggests a lower reaction threshold of CC probabilities. The CC cross sections are larger than the CS results within the entire energy range, demonstrating that the Coriolis coupling effect can effectively promote the He + HeH(+) reaction.
基于新的势能面[Liang 等人,J. Chem. Phys.2012, 136, 094307],采用含时量子波包方法研究了 He + HeH(+)(X(1)Σ(+))反应的动力学。计算了耦合通道(CC)和离心突发(CS)反应几率以及总积分截面。比较了考虑和不考虑科里奥利耦合的结果,表明 K 态数 N(K)(K 是总角动量 J 在体坐标系 z 轴上的投影)对反应阈值有显著影响。共线几何中 He + HeH(+)反应的每个 N(K)的有效势能分布曲线表明,随着 N(K)的增加,势垒高度逐渐降低。在总角动量 J = 50 时,碰撞能为 0.27-0.36 eV 的 CC 和 CS 几率密度分布的计算时间演化清楚地表明 CC 几率的较低反应阈值。在整个能量范围内,CC 截面大于 CS 结果,表明科里奥利耦合效应能有效促进 He + HeH(+)反应。