Y^nO(n=16,17,18)分子基态的结构与分析势能函数  

Structures and analytical potential energy functions of the ground states of Y^nO(n=16,17,18) molecules

作　　者：许永强[1] 彭伟成[1] 武华[1] 

机构地区：[1]赣南师范学院物理与电子信息学院,赣州341000

出　　处：《原子与分子物理学报》2011年第6期1003-1008,共6页Journal of Atomic and Molecular Physics

基　　金：江西省教育厅科技计划项目(GJJ10240)

摘　　要：应用密度泛函理论的B3LYP方法,在Y的有效原子实势近似下,(O原子选用6-311+G(3df)和AU-cc-PVTZ基组,优化计算了Y"O(n=16)分子基态的能量,平衡结构,和谐振频率.根据原子分子反应静力学原理,导出了Y"O(n=16,17,18)分子基态的合理离解极限.通过优化计算结果和已有的实验数据对比,得出CRENBL ECP/AUG-cc-PVTZ混合基组为对体系进行计算的最优基组.基于此,在B3LYP/CRENBL ECP/AUG-cc-PVTZ水平也对Y"O(17,18)进行了结构优化和频率计算,同时对YO分子基态的势能面进行了单点能扫描.并采用最小二乘法拟合得到了相应的Murrell-Sorbie势能函数.计算出了相应的力常数(f_2,f_3,f_4)和光谱常数(B_e,α_e,ω_e,ω_ex_e,D_e).结果与已有的实验数据吻合的很好.Based on effective core potential of Y atom, selecting 6-311＋G（3df）, AUG-cc-PVTZ basis sets for O atom, the energies, equilibrium structure and harmonic frequency of the ground states of YnO （n= 16） molecules are calculated using density functional theory（B3LYP）. Based on the theory of atom- ic and molecular statics, the reasonable dissociation limit of the ground states of YnO（n=16,17,18） molecules are derived. By comparing the results of calculations with the existing experimental values, we consider that the mixed basis sets CRENBL ECP/AUG-cc-PVTZ is the most suitable for the calcula- tion of the molecules. Consequently, optimization and frequency calculation have been done for YnO（n= 17,18） and the potential energy surface of the ground states of YO molecule has been scanned at the B3LYP/ CRENBL ECP/AUG-cc- PVTZ level of the theory. The potential energy curves of the ground states are obtained by least square fitting to the Murrell-Sorbie potential energy function. The spectro- scopic constants （B,, ae, co., w,Z. ,De） and force constants （（fz, experimental results. It indicate that the results of calculations mont~｜ rl^t~ f3, f4 ）are calculated and compared with are in good agreement with the experi-

关 键 词：YnO(n=16 17 18)分子基态 分子结构 分析势能函数 光谱常数 

分 类 号：O561.1[理学—原子与分子物理]