H+Li2: 一个典型的释能反应体系及其含时动力学研究

利用含时量子波包动力学理论在HLi₂ 基态势能面上研究了H+Li₂ → LiH+Li 反应的动力学性质. 计算得到了体系在0-0.4 eV 范围内J = 0 不同振动量子数(v = 0, 1, 2, 3), v = 0 不同转动量子数(J = 0, 5, 10,15) 下的反应概率、积分反应截面和热速率常数, 在此基础上讨论了释能反应的反应阈能随总角动量量子数的变化规律以及振动量子数对反应概率的影响等问题. 研究发现, 随着转动量子数的增大, 反应阈能也在逐渐增大; 然而随着振动量子数的增大, 由于反应为释能反应, 反应发生的概率却在逐渐减小. 分析了碰撞能对积分散射截面的影响以及温度对反应速率常数影响的规律.

H + Li2: a typical exothermic reactive system and its time-dependent dynamics investigation

In this paper, the time-dependent wave-packet method is used to study the three-dimensional dynamical properties of the H+Li₂ reactive system on its ground state potential energy surface. The reaction probabilities for J=0 with different vibrational quantum numbers v=0, 1, 2, 3 and for v=0 with different total rotational quantum numbers, integral cross sections and rate constants are calculated for collision energies in a range between 0 and 0.4 eV. The features of the reaction probabilities and reaction threshold energy are analyzed. The results show that the vibrational excitation has a certain inhibitory effect on the reaction process and the reaction threshold energy increases with the increase of J. These phenomena are associated with the type of the exothermic reaction of the reactive system. The influence of the collision energy on the integral cross sections and the effect of the temperature on reaction rate constants are also investigated.