苯羧酸一级电离Gibbs自由能的密度泛函研究  

DFT Calculation on Gibbs Free Energy of Primary Ionization of Benzene Carboxylic Acids in Aqueous Solution

作　　者：位艳宾[1] 何伟平[1] 孙婷婷[1] 刘焕[1] 李想 WEI Yanbin;HE Weiping;SUN Tingting;LIU Huan;LI Xiang(School of Chemical Engineering,Xuzhou College of Industrial Technology,Xuzhou 221140,China;Jiangsu Province Engineering Technology Research and Development Center of New Chemical Materials,Xuzhou 221140,China)

机构地区：[1]徐州工业职业技术学院化学工程学院,江苏徐州221140 [2]江苏省化工新材料工程技术研究开发中心,江苏徐州221140

出　　处：《化工技术与开发》2022年第6期10-15,共6页Technology & Development of Chemical Industry

基　　金：徐州市重点研发计划(社会发展)项目(KC18152);校级产业研发项目(KJCCYYF2019092305,KJCCYYF2019092308)。

摘　　要：采用密度泛函理论的B3LYP/6-311G(d)方法并考虑色散校正,优化得到了苯羧酸分子及其一级电离产物的几何结构,振动频率分析计算结果证实所得结构均为稳定构型,并获得了各物种在气相状态下的Gibbs自由能。基于B3LYP/def2TZVP级别计算出了CM5原子电荷,采用uESE溶剂模型,计算了12种苯羧酸(含苯甲酸)在水中的溶解自由能。在前述计算的基础上,进行了苯羧酸一级电离Gibbs自由能的密度泛函分析。分析结果表明,苯羧酸一级电离产物的Gibbs自由能与分子内氢键密切相关;同时,一级电离Gibbs自由能的大小,还与反应物是否存在分子内氢键,以及产物形成氢键的位置等因素有关。The geometric configurations of benzene carboxylic acids and their primary ionization products were optimized at the level of B3LYP/6-311G(d) with empirical dispersion correction methods.Gibbs free energies of each species in gas state were obtained by frequency calculation,which confirmed that all the configurations were the stable ones.Based on the program uESE solvent model and the gas-phase CM5 atomic charges,Gibbs free energies of dissolution of 12 benzene carboxylic acids,included benzoic acid,were calculated at the level of B3LYP/def2TZVP.According to the result of calculation above,Gibbs free energies of primary ionization of benzene carboxylic acids in aqueous solution were analyzed.The result indicated that Gibbs free energy of ionization was closely related to the intramolecular hydrogen bond of product.Moreover,Gibbs free energy of primary ionization was related to other factors,such as intramolecular hydrogen bonds in the ionization reactant,site of the intramolecular hydrogen bond in the ionization product and so on.

关 键 词：密度泛函 苯羧酸 Gibbs自由能 电离 

分 类 号：O641[理学—物理化学]