He-LiH体系转动非弹性碰撞的理论研究

在单双迭代耦合簇CCSD(T)势能面的基础上,运用密耦方法讨论了He-LiH体系的转动非弹性碰撞.计算结果表明,对LiH分子j=0→j′跃迁,跃迁截面主要由各向异性的短程相互作用和长程的“软”排斥共同作用的结果,未见明显的长程吸引势贡献.态－态跃迁总截面表现出振荡结构,长程“软”排斥分波只对j=0向j′=1、2、3的跃迁总截面有较大贡献,而j′≥ 4跃迁的积分截面则几乎由各向异性的短程部分贡献.

Theoretical Studies of Rotationally Inelastic Collisions of LiH with He

The process of rotationally inelastic collision of He-LiH complex has been discussed with close-coupling method based on the CCSD(T) potential energy surface. State-to-state partial and integral cross sections are calculated. The partial cross sections show that the transition cross sections of j=0→j′originate from the contributions of both the anisotropic short-range interaction and the long-range “soft” repulsion, while there is no evident for the long－range attraction. The state-to-state integral cross sections display an oscillatory structure. The long-range “soft” repulsion partial cross sections have only an effect on the integral cross sections for j=0→j′=1,2,3,and the cross sections for j′≥ 4 are almost decided by the anisotropic short-range partial.