基态S_3分子的结构与解析势能函数(英文)

Structure and analytic potential energy function for ground state of S_3 molecule

本文采用Gaussian03 B3P86方法,在6-311++G(3d2f)基组水平上,对S3分子进行几何优化理论计算,计算结果表明S3分子基态1A1最稳定的构型为C2V构型,其离解能为10.8372 eV,能量最小值为-1193.19946 a.u.,计算还得到了谐振频率、力常数,计算结果与实验值符合得很好.在此基础上利用多体展式理论方法得到了S3分子的解析势能函数和等值势能图,势能函数正确反映了S3分子的构型与能量变化.

The equilibrium geometry, harmonic frequency, force constant, and dissociation energy for the ground state S3（ ^1A1）have been derived by Gaussian 03 program with the B3P86 method , based on the 6- 311 ＋ ＋ G（3d2f） basis set for N atom, S3 molecular has a bent （C2v^1A1） ground state structure with the angle of 118.33° and a ringed （D3h） structure with the angle of 60°. The calculations are in good agreement with experimental results. Dissociation limit is derived by atomic and molecular reaction statics, the analytical potential energy function of S3 has been derived based on the many-body expansion theory, The structure and energy of S3 molecular can correctly reappear on the potential surface.