A reliable ab initio potential energy surface and vibrational states for the ground electronic state of HgH2(X-1 Sigma(+)(g))

作者：Li H; Xie DQ^*; Guo H

来源：Journal of Chemical Physics, 2005, 122(14): 144314.

DOI：10.1063/1.1876132

A three-dimensional global potential energy surface for the ground (X (1)Sigma(g)(+)) electronic state of HgH2 is constructed from more than 13 000 ab initio points. These points are generated using an internally contracted multireference configuration interaction method with the Davidson correction and a large basis set. Low-lying vibrational energy levels of HgH2, HHgD, and HgD2 calculated using the Lanczos algorithm are found to be in good agreement with the available experimental band origins. The majority of the vibrational energy levels up to 9000 cm(-1) are assigned with normal mode quantum numbers. Our results indicate a gradual transition for the stretching vibrations from the normal mode regime at low energies to the local mode regime near 9000 and 8000 cm(-1) for HgH2 and HgD2, respectively, as evidenced by a decreasing energy gap between the (0,0,n(3)) and (1,0,n(3)-1) vibrational states and bifurcation of the corresponding wave functions.

• 出版日期2005-4-8
• 单位南京大学