Incorporating solvation effects into density functional theory: Calculation of absolute acidities
Incorporating solvation effects into density functional theory: Calculation of absolute acidities
复制标题
将溶剂化效应纳入密度泛函理论：绝对酸度的计算
DOI：
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
D. Case
中科院分区：
文献类型：
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作者：
W. Richardson;C. Peng;D. Bashford;Louis Noodleman;D. Case
描述了凝聚相中分子电子结构、溶剂化能和 pKa 值的计算方法。溶质的电子结构由密度泛函量子力学描述，环境影响的静电特征通过外部电荷分布和连续介质电介质进行建模。通过泊松-玻尔兹曼方程的有限差分解计算分子电荷分布模式产生的反应电势，并将其纳入自洽场程序中。在这里，我们报告了三组有机酸的结果，其 pKa 值范围超过 16 个 pH 单位。第一组提供蛋白质中可电离侧链的模型；第二组考虑用一到三个氯原子取代乙酸中的氢的影响；最终组由4-取代-双环-[2.2.2]-辛烷羧酸组成。 “绝对”pKa 值的成功预测对气相质子亲和力的计算和溶剂化响应提出了严格的要求。在某些情况下，当前模型显示出很大的错误，但总体而言，结果和趋势与实验非常吻合。简要讨论了将这种方法扩展到更复杂的系统（例如蛋白质）的前景。 © 1997 约翰威利父子公司。
An approach to the calculation of molecular electronic structures, solvation energies, and pKa values in condensed phases is described. The electronic structure of the solute is described by density functional quantum mechanics, and electrostatic features of environmental effects are modeled through external charge distributions and continuum dielectrics. The reaction potential produced by a mode of the molecular charge distribution is computed via finite-difference solutions to the Poisson-Boltzmann equation and incorporated into the self-consistent field procedure. Here we report results on three sets of organic acids, whose pKa values range over 16 pH units. The first set provides models for ionizable side chains in proteins; the second set considers the effects of substituting one to three chlorine atoms for hydrogens in acetic acid; and the final set consists of 4-substituted-bicyclo-[2.2.2]-octanecarboxylic acids. Successful prediction of “absolute” pKa values places stringent requirements on the computation of gas-phase proton affinities and on the response to solvation. In some cases the current model shows substantial errors, but overall the results and trends are in good agreement with experiment. Prospects for extending this approach to more complex systems such as proteins are briefly discussed. © 1997 John Wiley & Sons, Inc.
影响因子：
2.9
作者：
BASHFORD, D;CASE, DA;WRIGHT, PE
通讯作者：
WRIGHT, PE