Influence of Ion Solvation on the Properties of Electrolyte Solutions

It is widely appreciated that the addition of salts to water leads to significant changes in the thermodynamic and dynamic properties of these aqueous solutions that have great significance in biology and manufacturing applications. However, no theoretical framework currently exists that describes these property changes in an internally consistent fashion. In previous work, we developed a coarse-grained model of electrolyte solutions capable of reproducing basic trends on how salts influence the viscosity and water diffusion coefficient. The present work explores the predictions of this model for basic thermodynamic properties of electrolyte solutions, namely, the density, isothermal compressibility, and surface tension. On the basis of our model, we find that ion-specific effects on thermodynamics properties, and by extension the dynamics of electrolyte solutions, derive primarily from ion solvation.