PCln (n=-1,0,+1)分子离子基态的结构与势能函数

 基于Gaussian03计算软件,选用高角动量基函数6-311++g(df,pd),分别使用密度泛函理论UB3LYP和UB3P86,以及组态相互作用方法UCCSD-FC和UQCISD-FC,对PCl分子和PCl⁺,PCl^-离子基态进行了几何优化,进一步对其进行了频率计算和单点能扫描计算.用最小二乘法拟合得到了PCl^<em>n(n=-1,0,+1)分子离子基态的Murrell-Sorbie势能函数.与实验及理论结果比较表明,对PCl,PCl⁺分子离子基态光谱常数 (B_e,α_e,ω_e,ω_ex_e)的计算结果达到了很高的精度.文章还首次给出PCl^-分子离子基态光谱参数(B_e,α_e,ω_e,ω_ex_e)和PClⁿ(n=-1,0,+1)力常数(f₂,f₃,f₄)的理论数据,为PClⁿ(n=-1,0,+1)分子离子的更深层次研究和应用提供重要的理论基础.

The structure and potential energy function for the ground state of the PCl~n(n=-1,0,+1)

Based on the Gaussian03 calculation software,the density functional theory UB3LYP and UB3P86,configuration interaction method UCCSD-FC and UQCISD-FC have been used to optimize the possible ground-state structures of PCl molecule,PCl⁺ and PCl^- molecule ion with the 6-311++g(df,pd) basis sets respectively.Frequency and single-point energy scan for PCl^<em>n(n=-1,0,+1) have been calculated.Spectral parameters (B_e,α_e,ω_e,ω_eχ_e) of the PCl molecule and PCl⁺ ion ground state are obtained by least square fitting to the Murrell-Sorbie function.The results of calculation are in good agreement with experimental data.In this work,spectral parameters (B_e,α_e,ω_e,ω_eχ_e) of PCl^- and force constants (f₂,f₃,f₄) of PClⁿ(n=-1,0,+1) molecule ion for ground state are shown for the first time.This calculation may provide important theoretical basis for investigation and further study of PClⁿ(n=-1,0,+1).