BeF_(2)分子基态势能函数研究

Studies on the ground state analytical potential energy function for BeF_(2)molecule

利用密度泛函理论(DFT)B3LYP/aug-cc-pVTZ方法对BeF和BeF_(2)分子的结构及电子性质进行计算,得到BeF分子的基态电子态为X^(2)Σ^(+),平衡核间距R_(e)=0.1367 nm,BeF_(2)分子最稳定构型为D_(∞h)构型,基态电子态为X^(1)Σ_(g)^(+),离解能D_(e)=13.4 eV.利用最小二乘法拟合了BeF分子基态的Murrell-Sorbie势能函数,并得到其光谱数据与力常数.结合全局多体项展式方法,导出了基态BeF_(2)分子基态势能函数的解析表达式,该函数准确反映了BeF_(2)分子的结构以及静态反应特征,这些结果为进一步探索BeF_(2)的微观分子反应动力学提供了基础.

By using B3LYP/AUG-cc-pVTZ method,the equilibrium geometry and electronic properties of BeF and BeF_(2) molecules has been calculated.The results show that the ground state of BeF molecule is X^(2)Σ^(+),and its equilibrium nuclear distance R_(e) is 0.1367 nm.The stable structure of BeF_(2) molecule has D_(∞h) symmetry with its electronic ground state X^(1)Σ_(g)^(+) and the dissociation energy D_(e)=13.4 eV.The Murrell-Sorbie potential energy function of the BeF molecule in the ground state has been fitted by the method of least square fitting,and the spectral data and force constants have been obtained.Based on this,the ground state analytical potential energy function of the BeF_(2) molecule has been derived using the many-body expansion theory,which accurately describes the configuration and static reaction character for the BeF_(2) molecule.These results can pave the way for further research on the molecular reaction dynamics of BeF_(2) molecule.