李品钧1,黄雨淋
He-HF(1∑+)体系(=1)的二维势能面及特性
李品钧1,黄雨淋2
(1. 湛江幼儿师范专科学校 信息科学系,广东 湛江 524037;2. 安徽师范大学 物理与电子信息学院,安徽 芜湖 241000)
He-HF体系;势能面;相互作用势
表1 1.2 a0时拟合av5z基组下的势能点得到的解析势能面系数 a.u.
在建立三维势能面的过程中,共采用2 502个分子构型,拟合得到的总方均根差为0.112 7 cm-1,最大误差为0.805 2 cm-1.分段验证结果见表2. 由表2可以看出,势能值在0~600 cm-1范围内,拟合得到的最大误差为0.786 5 cm-1,方均根差为0.127 8 cm-1;在-20~0 cm-1范围内,最大误差为0.805 2 cm-1,方均根差为0.067 75 cm-1;当相互作用势小于-20 cm-1时,最大误差为0.537 4 cm-1,方均根差为0.079 47 cm-1.
表2 从头算CCSD(T)三维势能面拟合误差比较
分立位置表象方法是分立变量表象(DVR)方法的一种, DVR方法是将薛定谔方程进行离散化处理, 用带权重的正交多项式插值表示波函数.哈密顿量中的动能算符在分立位置表象中的矩阵元是
对一维薛定谔方程的求解转化为求解久期方程
利用Fortran语言编写程序对角化处理式(6),就可以得到HF分子在各位置格点上的波函数值.
文献[5-7]的工作都表明振动绝热势可以为相应的实验结果提供很好的解释;且HF分子的振动能量要比分子间的范德瓦尔斯模的能量大,分子间和分子内的核运动可以被认为是相互独立的. 因而对He-HF体系低振动态下的二维势能面计算应用振动绝热近似,振动平均He-HF势为
表3 振动绝热平均势拟合参数 a.u.
图1 He-HF体系()势能面等势图
表4 势能面稳定点以及与势能面稳定点比较
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LI Pinjun1,HUANG Yulin2
(1. Department of Information Science,Zhanjiang Preschool Education College,Zhanjiang 524037,China;2. School of Physics and Electronic Information,Anhui Normal University,Wuhu 241000,China)
He-HF system;potential energy surface;interaction energies
O562.4
A
10.3969/j.issn.1007-9831.2022.06.008
1007-9831(2022)06-0044-05
2022-03-05
湛江市非资助科技攻关专题(2020B01086);2020年度广东省普通高校特色创新项目(2020KTSCX351)
李品钧(1979-),男,贵州福泉人,讲师,从事基础物理研究.E-mail:pingyuejushi@126.com