A multistate empirical valence bond model for solvation and transport simulations of OH- in aqueous solutions.

Department of Chemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
Physical Chemistry Chemical Physics (Impact Factor: 3.83). 11/2009; 11(41):9420-30. DOI: 10.1039/b907859b
Source: PubMed

ABSTRACT We describe a new multistate empirical valence bond (MS-EVB) model of OH(-) in aqueous solutions. This model is based on the recently proposed "charged ring" parameterization for the intermolecular interaction of hydroxyl ion with water [Ufimtsev, et al., Chem. Phys. Lett., 2007, 442, 128] and is suitable for classical molecular simulations of OH(-) solvation and transport. The model reproduces the hydration structure of OH(-)(aq) in good agreement with experimental data and the results of ab initio molecular dynamics simulations. It also accurately captures the major structural, energetic, and dynamic aspects of the proton transfer processes involving OH(-) (aq). The model predicts an approximately two-fold increase of the OH(-) mobility due to proton exchange reactions.

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