The molecular structure and the analytical potential energy function of S-2 and S-3

• 来源期刊: 中国物理（英文版）
• 关键词: S-2 S-3 molecular structure potential energy function
• 年，卷（期）: 2007,（8）
• 页码范围: 2356-2360
• 页数: 5页
• 语种: 英文

摘要

In this paper, the equilibrium geometry, harmonic frequency and dissociation energy of S-2 and S-3 have been calculated at QCISD/6-311++G(3d2f) and B3P86/6-311++G(3d2f) level. The S-2 ground state is of 2Ⅱg, the S-3 ground state is of 2B1 and S-3 has a bent (C2V) structure with an angle of 115.65° The results are in good agreement with these reported in other literature. For S-3 ion, the vibration frequencies and the force constants have also been calculated. Base on the general principles of microscopic reversibility, the dissociation limits has been deduced. The Murrell-Sorbie potential energy function for S-2 has been derived according to the ab initio data through the leastsquares fitting. The force constants and spectroscopic data for S-2 have been calculated, then compared with other theoretical data. The analytical potential energy function of S-3 have been obtained based on the many-body expansion theory. The structure and energy can correctly reappear on the potential surface.