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Ion Sizes and Finite-Size Corrections for Ionic-Solvation Free Energies

Gerhard Hummer·Lawrence R. Pratt·Angel E. Garcia
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Abstract

Free energies of ionic solvation calculated from computer simulations exhibit a strong system size dependence. We perform a finite-size analysis based on a dielectric-continuum model with periodic boundary conditions. That analysis results in an estimate of the Born ion size. Remarkably, the finite-size correction applies to systems with only eight water molecules hydrating a sodium ion and results in an estimate of the Born radius of sodium that agrees with the experimental value.

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Gerhard Hummer, Lawrence R. Pratt, Angel E. Garcia. 1997-09-30. Ion Sizes and Finite-Size Corrections for Ionic-Solvation Free Energies. https://doi.org/10.1063/1.475219

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