Sheng X W, Li P, Tang K T
Institute of Atomic and Molecular Physics, Sichuan University, Chengdu, Sichuan 610065, People's Republic of China.
J Chem Phys. 2009 May 7;130(17):174310. doi: 10.1063/1.3126779.
The ground state van der Waals potentials of the Hg-RG (RG = He,Ne,Ar,Kr,Xe) systems are generated by the Tang-Toennies potential model. The parameters of the model are calculated from the potentials of the homonuclear mercury and rare-gas dimers with combining rules. The predicted spectroscopic parameters for these mercury rare-gas complexes are in good agreement with available experimental values, except for Hg-He. In the repulsive and potential well regions, the predicted potential energy curves agree with the available experimental hybrid potentials, but they differ in the long range part of the potential. On the other hand, the present potentials are in agreement with the ab initio CCSD(T) calculations in the long range part of the potential, but there are some differences in the short repulsive regions. According to the present theory, the reduced potential curves of these five systems, including Hg-He, are almost identical to each other. This reduced potential curve can also describe, within a few percent, the five reduced potentials obtained from the ab initio CCSD(T) calculations. These reduced potentials have a potential bowl that is wider than that of the rare-gas dimers, but narrower than the mercury dimer.
Hg-RG（RG = He、Ne、Ar、Kr、Xe）体系的基态范德华势由Tang-Toennies势模型生成。该模型的参数通过同核汞和稀有气体二聚体的势利用组合规则计算得出。这些汞稀有气体配合物的预测光谱参数与现有的实验值吻合良好，但Hg-He除外。在排斥区和势阱区，预测的势能曲线与现有的实验混合势一致，但在势的长程部分有所不同。另一方面，当前的势在势的长程部分与从头算CCSD(T)计算结果一致，但在短程排斥区存在一些差异。根据当前理论，包括Hg-He在内的这五个体系的约化势曲线几乎彼此相同。这条约化势曲线还能在百分之几的误差范围内描述从从头算CCSD(T)计算得到的五个约化势。这些约化势具有一个比稀有气体二聚体的势阱更宽但比汞二聚体的势阱更窄的势阱。
