La_2分子结构与基态分子势能函数

Molecular Structure and Analytic Potential Energy Function for Ground State X^1Σ_g^+ of La_2 Molecule

用相对论有效原子实势 ,在密度泛函理论 (DFT)和组态相关理论 (QCISD)水平上优化计算了La2分子的结构 .根据原子分子反应静力学原理 ,导出La2 分子可能的电子状态和离解极限 ,用DFT中的B3LYP方法计算了基态X1Σ+ g 势能曲线 ,拟合得到Murrell Sorbie解析势能函数 ,并首次计算得到基态X1Σ+ g 的谐振频率、热力学性质。

The equilibrium geometry of La_2 molecule has been firstly calculated at the levels of density function theory (DFT) and configuration interaction theory QCISD with the relativistic effective core potential. The possible electronic state and its reasonable dissociation limit for the ground state of La_2 are determined based on atomic and molecular reaction statics. The potential energy curve for the ground state X^1Σ^+_g has been calculated with B3LYP method density functional theory. Murrell-Sorbie analytic potential energy function has been derived with a nonlinear least-square fit. The harmonic frequency, thermodynamic property, force constant and spectroscopic data of the ground state X^1Σ^+_g have been derived for the first time.