有机小分子偶极矩影响因素研究  

A study of the influential factors on the dipole moments of small organic

作　　者：付新梅[1] 李燕[2] 王景辉[2] 

机构地区：[1]大连理工大学精细化工国家重点实验室,辽宁大连116023 [2]大连理工大学化工学院,辽宁大连116023

出　　处：《计算机与应用化学》2015年第4期408-412,共5页Computers and Applied Chemistry

基　　金：国家自然科学基金资助项目(10801025)

摘　　要：分子内部电荷分布不均使分子具有极性,分子的极性又影响了分子间的氢键、范德华力等相互作用力,进而影响宏观物质的化学特性,如化合物的溶解性、正辛醇,水分配系数和液相色谱保留行为等。化学特性的本质来源于其分子微观电荷状态,而偶极矩正是反映分子内电荷分布情况的重要物理量,因此估测分子的偶极矩十分重要。文中选取8种结构类型共107个分子,用Dragon软件计算出每个分子的929个分子参数,用多元线性回归法和主成分分析法分析参数对偶极矩值的影响。分析结果表明,相比主成分分析法,多元线性回归的stepwise法为最优建模方法。该模型统计结果良好(R^2=0.878,SEC=0.330,F=65.697),预测结果良好(R^2=0.792,SEP=0.665)。结果表明分子的平均原子电负性、距离矩阵参数、分子的组成、相邻原子的对称性、价键连接指数和分子的电性拓扑指数是影响偶极矩的主要因素。建立的最优回归模型对有机小分子的偶极矩具有很好的预测能力,对研究物质的宏观化学特性有一定的帮助作用。The asymmetrical charge distribution of a molecule makes sure of its certain polarity, which in turn influences the intermolecular forces like Hydrogen bond and Van der Waals force, and the resulted chemical properties like solubility, octyl alcohol-water distribution coefficient and chromatographic retention behavior of the corresponding macro material. The nature of chemical properties derives from molecular charge distribution, in which dipole moment is just a crucial physical quantity parameter reflecting the charge distribution of the molecule. So it is very important to explore the effect factors as well as to predict the values of dipole moment. Presently, a dataset composed of 109, 8 diversified structural types of small organic molecules were built. Based on the 929 Dragon molecular indices we calculated for the molecules, two approaches including the principal component regression analysis （PCA） and multivariate linear regression （MLA） methods were applied on them to build models. Consequently, MLA exhibits better performance than PCA. In addition, among the 5 kinds of multivariate linear regression methods, stepwise regression analysis obtains the most satisfactory statistical results （with R2=0.713, SEC=0.550, F=32.284 for the training set, and R2=0.723, SEP=-0.608 for the test set, respectively） indicating both proper internal and external predictability. The result shows that atomic electronegativity, distance matrix, atomic composition, neighborhood symmetry, valence connectivity index and eleclrotopological state indices are the principal effect factors, which information and model, we hope, are helpful for further study of chemical properties on small organic molecule.

关 键 词：偶极矩 分子参数 多元线性回归法 主成分分析法 

分 类 号：O656.4[理学—分析化学] O641[理学—化学]