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Quasi-Chemical Theory and Implicit Solvent Models for Simulations

Lawrence R. Pratt·Susan B. Rempe
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Abstract

A statistical thermodynamic development is given of a new implicit solvent model that avoids the traditional system size limitations of computer simulation of macromolecular solutions with periodic boundary conditions. This implicit solvent model is based upon the quasi-chemical approach, distinct from the common integral equation trunk of the theory of liquid solutions. The physical content of this theory is the hypothesis that a small set of solvent molecules are decisive for these solvation problems. A detailed derivation of the quasi-chemical theory escorts the development of this proposal. The numerical application of the quasi-chemical treatment to Li$^+$ ion hydration in liquid water is used to motivate and exemplify the quasi-chemical theory. Those results underscore the fact that the quasi-chemical approach refines the path for utilization of ion-water cluster results for the statistical thermodynamics of solutions.

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Lawrence R. Pratt, Susan B. Rempe. 1999-09-03. Quasi-Chemical Theory and Implicit Solvent Models for Simulations. https://doi.org/10.1063/1.1301528

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