基态H2O+的全域多体势能面

基态H₂O⁺分子离子是重要的星际反应中间体.用MRCISD/cc-pVTZ先计算H₂O⁺势能面,然后拟合成多体势能函数.全域势能面能很好地描述基态H₂O⁺的行为.与两条反应通道的实验能变和其构型翻转反应能垒比较,表明计算结果与实验值相符.对计算点完成了力场的多项式拟合,对其振动模式进行了分析

Global Many-body Potential Energy Surface of Ground State H2O+

Ground state H 2O + is an important intermediate in atmospheric and interstellar chemistry. An accurate global ab initio potential energy surface is presented for the ground state H 2O + molecular ion. The calculations were based on the externally contracted multi-reference configuration interaction method with all single and double excitations(EC-MRCISD) with cc-pVTZ basis. The surface was fitted as many-body function form suggested by Aguado and Paniagua and well indicates the behavior of the ground state H 2O +. The calculated results of energy changes in the dissociation reaction and the active energy of geometry-inverse reaction are coincident with experimental results. Besides, the data points were fitted to a polynomial force field, and analysis of normal vibration modes was performed.