OH^(-)+CH_(3)I反应的量子动力学研究:反应概率、积分截面和能量有效性  

Quantum Dynamics Study of OH^(-)+CH_(3)I Reaction:Reaction Probability,Integral Cross Section,and Energy Efficacy

作　　者：饶深琰 王敦友[1] Shenyan Rao;Dunyou Wang(College of Physics and Electronics,Shandong Normal University,Jinan 250014,China)

机构地区：[1]山东师范大学物理与电子科学学院,济南250014

出　　处：《Chinese Journal of Chemical Physics》2023年第2期169-174,I0054,共7页化学物理学报（英文）

基　　金：This work is supported by the National Natural Science Foundation of China(No.11774206);the Taishan Scholarship Fund of Shandong Province.The calculations are carried out at the Shenzhen Supercomputer Center in China.

摘　　要：本文采用含时的量子动力学波包方法研究了OH^(-)+CH_(3)I反应的反应概率、积分截面和能量有效性.基于S_(N)2反应键同步打断和形成的机制,建立了四自由度动力学模型.发现反应概率随碰撞能量的变化而减小,这是具有负能垒的反应的典型特征.利用该模型计算得到的基态积分反应截面与准经典轨迹结果吻合很好.在相同的总能量下,振动激发态和基态的积分反应截面比表明,CH_(3)-I的振动能比体系的平动能对提高反应性能更有效,而平动能对反应性能的贡献又比C-H_(3)的振动能更有效.突然矢量投影模型的预测证实了上述能量有效性的顺序.We investigate the reaction probability,integral cross section,and energy efficiency of theOH^(-)+CH_(3)I reaction using the time-dependent quantum dynamics wave packet method.A fourdegree-of-freedom dynamics model is developed for this study due to the synchronized S_(N)2 bond-breaking and formation mechanism.We find that the reaction probability decreases as a function of the collision energy,which is a typical character of reactions with a negative energy barrier.The ground-state integral cross section calculated using this model is in excellent agreement with the quasi-classical trajectory results.The integral cross-section ratios of the vibrational excitations over the ground state,at the same equal amount of total energy,indicate that the vibrational motion of the CH_(3)−I is more efficient in enhancing the reactivity than the translational motion,which,in turn,has a bigger contribution to the reactivity than the C−H_(3) vibrational motion.The energy efficacy order in the reactivity is confirmed by the sudden vector model prediction.

关 键 词：量子动力学 反应概率 积分截面 能量有效性 负能垒 

分 类 号：O643.1[理学—物理化学]