HYDROPHOBIC HYDRATION - INHOMOGENEOUS WATER-STRUCTURE NEAR NONPOLAR MOLECULAR SOLUTES

A potential of mean force (PMF) expansion is used to predict the water structure near nonpolar solutes having different shapes and molecular conformations. The decomposition of n-particle PMFs into pair and tri plet contributions describes well the hydration of those solutes consi sting of nonbonded clusters, but not covalently bonded molecules. Alte rnative proximity approximations are devised based on the local depend ence of the water structure on solute shape and excluded volume. Accur ate predictions obtained using these proximity approximations demonstr ate that water organization is only locally sensitive to structural de tails of nonpolar solutes.