SiO_2分子的基态(X^1A_1)结构与分析势能函数  

Structure and analytic potential energy function for the ground state of SiO_2 molecule

作　　者：伍冬兰[1] 程新路[1] 杨向东[1] 谢安东[1] 余晓光[2] 邓小辉[1] 

机构地区：[1]四川大学原子与分子物理研究所,成都610065 [2]井冈山学院数理学院,吉安343009

出　　处：《物理学报》2007年第1期147-151,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10376021);江西省教育厅科技项目(批准号:2006261);井冈山学院(批准号:J206161)资助的课题~~

摘　　要：应用群论及原子分子反应静力学方法推导了SiO2分子的电子态及其离解极限,采用B3P86方法,在6-311G**水平上,优化出SiO2基态分子稳定构型为单重态的C2V构型,其平衡核间距Re=RSi—O=0·1587nm,∠OSiO=111·2°,能量为-440·4392a.u..同时计算出基态的简正振动频率:对称伸缩振动频率ν(B2)=945·4cm-1,弯曲振动频率ν(A1)=273·5cm-1和反对称伸缩振动频率ν(A1)=1362·9cm-1.在此基础上,使用多体项展式理论方法,导出了基态SiO2分子的全空间解析势能函数,该势能函数准确再现了SiO2(C2V)平衡结构.The equilibrium geometry of SiO and SiO2 molecule has been calculated on the computational levels of density functional theory （DFT）. The possible electronic state and reasonable dissociation limit for the ground state of SiO and SiO2 X^1 A1 molecule are determined based on atomic and molecular reaction statics. And Murrell-Sorbie analytic potential energy function of SiO molecule has been derived through the least-square fitting to ab initio data. Similarly, the harmonic frequency has been calculated, and the analytic potential energy function of SiO2 molecule has been derived using many-body expansion theory.

关 键 词：SiO2分子 多体项展式理论 解析势能函数 

分 类 号：O561[理学—原子与分子物理]