PCl_X(X=1,2)分子基态的结构与势能函数

Structure and Potential Energy Function of PCl_X(X=1,2) Molecular Ground State

采用单双取代的二次组态相互作用(QCISD)方法,使用多种基组对PClX(X=1,2)分子基态结构进行优化计算,选出最优基组6-311+G(df)和6-311G(df)分别对PCl和PCl2分子的离解能、谐振频率和力常数等进行计算,结果与实验值符合很好.在此基础上推导出PCl2分子基态的多体展式势能函数,其等值势能图正确反应了PCl2分子的结构特征及势阱深度,进一步讨论Cl+PCl和P+ClCl分子反应的势能面特征.这些结果可用于微观反应动力学的研究.

QCISD method is used to optimize possible ground-state structures of PC1 and PC12 molecule with multiple basis sets. Dissociation energy, harmonic frequency and force constants are calculated with 6-311 ＋ G （dr） and 6-311G （dr） basis sets, respectively. They agree with experimental observations well. Potential energy functions of PC12 are derived from many-body expansion theory. Potential energy curves verify structure characteristics and potential depth. Cl＋ PCl and P ＋ ClCl based on molecular reaction potential energy surface are discussed. It describes molecular reaction dynamics successfully.