Langevin dipoles model for ab initio calculations of chemical processes in solution: Parametrization and application to hydration free energies of neutral and ionic solutes and conformational analysis in aqueous solution
Langevin dipoles model for ab initio calculations of chemical processes in solution: Parametrization and application to hydration free energies of neutral and ionic solutes and conformational analysis in aqueous solution
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DOI：
10.1021/jp9705075
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发表时间：
1997-07-10
影响因子：
3.3
通讯作者：
Warshel, A
中科院分区：
文献类型：
--
作者：
Florian, J;Warshel, A
提出了一种新的朗之万偶极子(LD)模型的参数化方法，用于水溶液中化学过程的从头计算。该参数化在迭代(ILD)和非迭代(NLD)版本的LD模型中实现。新的参数化训练集包括44个中性和39个离子溶质的溶剂化自由能，这些溶质包含C，O，N，P，S，F和Cl原子。模型的性能是通过检查它代表整个训练集的能力，结构相关化合物的pK(A)差异，以及1，2-乙二醇(乙二醇)的溶剂化能的构象相关变化来评估的。文中还讨论了溶质极化和电子关联的影响。研究发现，该模型的总体性能与Tomasi及其同事的PCM连续介质模型相当或略好。然而，LD模型对溶剂分子的简化显式表示可能使人们对不同溶剂效应的分子起源有更清晰的认识，而不是连续介质模型。该模型的当前版本可以作为独立程序使用，具有来自高斯或相关程序的标准输出。
A new parametrization of the Langevin dipole (LD) model is developed for abh initio calculations of chemical processes in aqueous solution. This parametrization is implemented in both the iterative (ILD) and noniterative (NLD) versions of the LD model. The training set for the new parametrization encompassed solvation free energies of 44 neutral and 39 ionic solutes that contained the C, O, N, P, S, F, and Cl atoms. The performance of the model is assessed by examining its ability to represent the overall training set, pK(a) differences of structurally related compounds, and conformation-related changes in the solvation energy of 1,2-ethanediol (glycol). The effects of solute polarization and electron correlation are also discussed. The overall performance of the model is found to be comparable or slightly better than the PCM continuum model of Tomasi and co-workers. However, the simplified explicit representation of solvent molecules of the LD model may allow one to gain a somewhat clearer insight into the molecular origin of different solvent effects than that obtained by continuum models. The present version of the model can be used as a stand alone program with the standard output from the Gaussian or related programs.