Murrell-Sorbie势下He-HCl碰撞体系微分散射截面的研究

根据在CCSD(T)/aug-cc-pVQZ理论水平下计算的He-HCl相互作用能数据,作者采用Murrell-Sorbie势函数形式拟合了He原子与HCl分子相互作用的各向异性势,并与其它势模型进行了比较;然后采用公认的精确度较高的CC近似方法计算了He-HCl碰撞体系的微分散射截面,总结了非弹性微分散射截面的变化规律.研究表明:采用拟合的各向异性势计算的微分散射截面与实验结果符合得很好.拟合势不但表达形式简洁,而且较好地描述了He-HCl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相互作用的机制有一定的参考价值.

Study of the differential scattering cross sections of Murrell-Sorbie potential for He-HCl system

We fit the anisotropic interaction potential based on the Murrell-Sorbie potential function for He-HCl system by applying the interaction energy data,which are calculated at the theoretical level of the single and double excitation coupled-cluster method with noniteractive perturbation treatment of triple excitation CCSD(T).The new potential model is compared with other potential models.The differential scattering cross sections for collisions between He atoms and HCl molecules are calculated by using CC(Close-Coupling) method.Furthermore,the changing regularity of the inelastic differential scattering cross sections is summed up.The DCS calculated by using the fitted anisotropic potential is in agreement with the existing experimental data.The fitted potential possesses not only advantage of the simpler function form but also is characteristic of expressing interaction better for He-HCl system,and that is more easier to determine the potential parameters based on the results of ab initio calculation for collision systems.Therefore,this work has some reference value for probing the interaction mechanism of atoms and molecules.