SO 分子的结构、光谱常数和势能函数

摘要

Based on the Gaussian09 calculation software, B3LYP 、CCSD and QCISD method has been used to optimize the possible ground -state structures of SO molecule with the 6-311+G(2df) basis sets.Frequency and single-point energy scan for SO have been calculated .Spectral parameters ( Be ,αe ,ωe ,ωeχe ) of the SO ground state are obtained by least square fitting to the Murrell -Sorbie function , All calculation results are in good agreement with experimental data.In this work, spectral parameters (Be,αe,ωe,ωeχe) and force constants (f2,f3, f4 ) of SO for ground state are shown for the first time .This calculation may provide a good testing ground for investigation of SO later .%采用Gaussian09软件，选用密度泛函的B3LYP方法及组态相互作用的CCSD和QCISD方法，配有多种基组对SO分子基态进行几何优化，选出B3LYP/6-311＋G（2df）方法，进行谐振频率和单点能扫描计算，利用此数据拟合了SO分子的M-S势能函数，其拟合曲线与单点势能值符合很好。本文计算得到的核间距R、光谱常数B e ，αe ，ωe ，ωeχe的结果与文献值、实验值比较达到了更高的精度，并首次计算出了力常数f2，f3，f4，这些结果可为三原子分子及动力学的研究提供有力的理论依据。