【摘要】 应用量子化学方法 MP2/6-311++G（d,p）//B3LYP/6-31+G（d,p）和原子-键电负性均衡浮动电荷分子力场（ABEEM/MM）,对[Na（H₂O）n]+（n=3～8）,[Na（NMA）n]+（n=3～8）和[Na（NMA）n（H₂O）m]+（n+m=4,6）（NMA=氮-甲基乙酰胺）体系的结构、结合能和电荷分布进行研究.在计算结果的基础上,构建上述体系的ABEEM/MM可极化势能函数,优选并确定相关参数.结果表明,ABEEM/MM的计算结果与量子化学的计算结果相符:Na+与配体间距离的平均绝对偏差（AAD）小于0. 007 nm,相对均方根偏差（RRMSD）小于3. 5%,夹角的AAD小于2. 4°,RRMSD小于2. 0%,结合能的AAD小于8. 9 k J/mol,RRMSD小于12. 4%;ABEEM/MM电荷分布与量子力学（QM）电荷分布的线性相关系数在0. 97以上.更多还原

【Abstract】 The geometries,binding energies of [Na（H₂O）n]+（n = 3—8）,[Na（NMA）n]+（n = 3—8）,[Na（NMA）n（H₂O）m]+（n+m = 4,6）（NMA = N-methylacetamide） were studied with the quantum chemical MP2/6-311++G（d,p）//B3 LYP/6-31 +G（d,p） level of theory and atom-bond electronegativity equalization method fused into molecular mechanics（ABEEM/MM） fluctuating charge force field. Based on the quantum chemical results, the polarizable ABEEM/MM potential energy functions of the above system were constructed,and the relative parameters were optimized and determined. The results show that the structures,binding energies,charge distributions obtained by ABEEM/MM are in good agreement with those from quantum chemical method（QM）. The average absolute deviations（AAD） of distances of Na+-ligand,angles,and binding energies are less than 0.007 nm,2.4°,8.9 kJ/mol,respectively. The relative root mean square deviations（RRMSD） of distances of Na+-ligand,angles,and binding energies are less than 3.5%,2.0%,12.4%,respectively. The linear correlation coefficients of the charge distributions from ABEEM/MM and QM are above0.97.更多还原