He-NO碰撞体系微分截面的理论计算  

Theoretical calculation of the differential cross section for He-NO collision system

作　　者：汪荣凯[1,2] 令狐荣锋[1] 杨向东[3] 

机构地区：[1]贵州师范大学理学院 [2]四川大学原子与分子物理研究所,成都610065 [3]四川大学原子与分子物理研究所

出　　处：《物理学报》2007年第4期2067-2072,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10574096);高等学校博士学科点专项科研基金(批准号:20050610010);贵州省教育厅自然科学基金(批准号:2005105)资助的课题.~~

摘　　要：首先用Huxley势函数形式拟合了在RCCSD(T)/aug-cc-pVTZ+bf理论水平下计算的He-NO相互作用能数据,获得了He原子与NO分子相互作用的各向异性势,然后采用密耦近似方法计算了He-NO碰撞体系的总微分截面、弹性微分截面和非弹性微分截面,并总结了微分散射截面的变化规律.结果表明,拟合势不但表达形式简洁,而且较好地描述了He-NO系统相互作用的各向异性特征;利用碰撞体系分子间势的量子化学从头计算结果,可解决势能参数难以确定的问题,对进一步研究原子与分子碰撞机理有一定参考价值.An anisotropie intermoleeular potential of the He-NO complex has been obtained by utilizing the Huxley analytic function to fit the intermolecular energy data, which have been calculated at the theoretical level of the RCCSD（T）/aug-cc-pVTZ ＋ bf. Then the total differential cross section, elastic differential cross section and inelastic differential cross section for collision between He atom and NO molecule have been calculated using close-coupling approximation. Finally, the law governing the change of the differential scattering cross section has been given. This study shows that the fitted anisotropic intermolecular potential not only possesses the advantage of a simpler function form but also offers a better description of the characteristic of interaction in He-NO system. At the same time, the difficult problem of determining the intermolecular potential parameters can be solved on the basis of the results of ab initio calculation for the collision systems. Therefore, the result obtained may be helpful for probing collision mechanism between atoms and molecules.

关 键 词：各向异性势 势能参数 密耦近似 微分截面 

分 类 号：O561[理学—原子与分子物理]