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- 2016
Ne—Na2分子基态势能面的从头算及分析拟合
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Abstract:
采用aug-cc-pVQZ(弥散函数的基组)/Na、aug-cc-pVDZ(弥散函数的基组)/Ne以及中点键函数的大基组,使用单、双迭代并包含三重激发微扰校正的耦合簇CCSD(T)理论方法,计算了Ne—Na2基态146个基态单点能.通过拟合96个参数,给出了Ne—Na2三原子分子体系的基态分子势能函数的解析表达式,并分析了其基态二维势能面的特性,在此基础上绘出了Ne—Na2三原子分子体系的三维势能曲线.计算结果表明,Ne—Na2基态势能面存在2个较浅的势阱,对应于θ=80°,R_Ne—Na=33a0处,势阱的阱深约为-6750×10-1cm-1和线型结构θ=0°,R_Ne—Na=10a0处,势阱深度约为-2341×10-3cm-1.此三原子分子体系的势能面呈现出弱的角度各向异性.
: By using the aug-cc-pVQZ(Augmented versions of the preceding basis sets with added diffuse functions) /Na, aug-cc-pVDZ(Augmented versions of the preceding basis sets with added diffuse functions)/Ne and the bond functions (bf) basis sets, three-dimensional potential energy surfaces (PES) for the interaction of rigid Na2with Ne are calculated.The coupled cluster singles-and-doubles with noniterative inclusion of connected triple [CCSD (T)] level of theory are used.The 146 ab initio points on the PES are fitted to a 96-parameter. The results of the interaction energy calculations and the corresponding fits to analytical functions are presented.Contour plots also are given. The deeper potential well is θ=80°,R_Ne—Na=33a0 with well depth -6750×10-1cm-1. The linear configuration with well depth -2341×10-3cm-1 is at θ=0°,R_Ne—Na=10a0. The whole potential energy surface exhibits weak anisotropy