AlF_2分子的结构性质与势能函数

运用密度泛函理论B3P86-311++G(3d2f)对基态AlF2分子的平衡电子结构进行优化计算,优化出AlF2分子稳定构型为C2V,电子态为2 A1,其平衡核间距Re=0.164 72nm、键角∠FAlF=119.614°、离解能14.656 2eV.并对它们的力常数及谐振频率进行进一步的计算.在推断出AlF2的离解极限基础上,应用多体展式理论方法,推导出基态AlF2分子的解析势能函数,该势能面准确再现了AlF2分子的结构特征和能量变化.分析讨论势能面静态特征得到:AlF+F→AlF2反应中不存在鞍点,为无阈能反应.

The Structure and Potential Energy Function Investigationon on AlF2 Molecule

Using the B3P86/6-311++G(3d2f),the possible ground-state structures of AlF2 molecule have been used to optimize.The results show that the ground state of AlF2 molecule is of C2v symmetry and of 2A1 state,whose angle,equilibrium nuclear distance and dissociation energy are 119.614°,0.164 72 nm and 14.656 2 eV.And the harmonic frequencies,force constants have been calculated.The present paper correctly determines the dissociation limits,based on group theory and atomic and molecular reactive statics(AMRS).Analytical potential energy functions for the ground states X2A1 of AlF2 have been derived using many-body expansion method.The structure and energy of AlF2 can correctly reappear on the potential surface.Molecular reaction kinetics of AlF+F based on the potential energy functions is discussed briefly.