烷烃小分子溶剂化自由能的快速计算  

Quick estimation of solvation free energies for small alkane molecules

作　　者：杨忠志[1] 于玲[1] 赵东霞[1] 

机构地区：[1]辽宁师范大学化学化工学院,辽宁大连116029

出　　处：《辽宁师范大学学报（自然科学版）》2010年第3期332-334,共3页Journal of Liaoning Normal University:Natural Science Edition

基　　金：国家自然科学基金项目(20633050;20873055;20703022)

摘　　要：将ABEEMσπ浮动电荷模型与generalized Born(GB)模型相结合,计算分子的溶剂化自由能.GB模型是一种连续介质模型,计算快速而简单,但是这种模型的计算精度却尚待提高.由于ABEEMσπ浮动电荷模型将分子的电荷区域进行了详细划分,分为原子区域、单键和双键区域、孤对电子区域,而且双键区域又更详细地分为1个σ键和4个π键区域,充分考虑了在外界环境发生变化的情况下,分子内部各个原子电荷重新排布,因而极大地提高了GB模型的计算精度.利用该方法快速准确地计算了几个烷烃小分子的溶剂化自由能.This paper reports an effective way to improve the accuracy of the generalized Born（GB）model in use of a fluctuating charge（FQ）model-the ABEEMσπ model（atom-bond electronegativity equalization method）.The GB model is a continuum model which treats the solvent as a continuous medium having the average properties of the real solvent,so the calculation of solvation free energy with this model is simple and rapid.However,the accuracy of this model requires some improvements.The charge regions of one molecule in ABEEMσπ model are explicitly presented by different sites：atoms,single bonds,double bonds,and lone-pairs,especially for double bonds with one σ and four π bond sites.Moreover,the partial atomic charges provided by the ABEEMσπ model can flow through chemical bonds from one atomic center to another based on the local electrostatic environment surrounding each atom,so accurate and rapid calculations have been performed for series of compounds involving several alkane molecules by ABEEMσπ-GB/SA method.

关 键 词：浮动电荷模型 GB/SA模型 溶剂化自由能 极化 

分 类 号：O641.121[理学—物理化学]