The equilibrium geometries, potential energy curves, spectroscopic dissociation energies of the ground and low-lying electronic states of He2, He2^+ and He2^++ are calculated using symmetry adapted cluster/symmetry...The equilibrium geometries, potential energy curves, spectroscopic dissociation energies of the ground and low-lying electronic states of He2, He2^+ and He2^++ are calculated using symmetry adapted cluster/symmetry adapted cluster-configuration interaction (SAC/SAC-CI) method with the basis sets CC-PV5Z. The corresponding dissociation limits for all states are derived based on atomic and molecular reaction statics. The analytical potential energy functions of these states are fitted with Murrell-Sorbie potential energy function from our calculation results. The spectroscopic constants Be, αe, ωe, and ωeχe of these states are calculated through the relationship between spectroscopic data and analytical energy function, which are in well agreement with the experimental data. In addition, the origin of the energy barrier in the ground state X^I∑9^+ of He2^++ energy curve are explained using the avoided crossing rules of valence bond model.展开更多
基金Supported by the Natural Science Foundation of Shaanxi Province of China under Grant No. 2009JM1007
文摘The equilibrium geometries, potential energy curves, spectroscopic dissociation energies of the ground and low-lying electronic states of He2, He2^+ and He2^++ are calculated using symmetry adapted cluster/symmetry adapted cluster-configuration interaction (SAC/SAC-CI) method with the basis sets CC-PV5Z. The corresponding dissociation limits for all states are derived based on atomic and molecular reaction statics. The analytical potential energy functions of these states are fitted with Murrell-Sorbie potential energy function from our calculation results. The spectroscopic constants Be, αe, ωe, and ωeχe of these states are calculated through the relationship between spectroscopic data and analytical energy function, which are in well agreement with the experimental data. In addition, the origin of the energy barrier in the ground state X^I∑9^+ of He2^++ energy curve are explained using the avoided crossing rules of valence bond model.