Estimation and interpretation of infinite dilution solute-solvent interaction enthalpies in non-electrolyte aqueous solutions

An empirical strategy has been developed for estimating the enthalpy and the volume requirement for the formation of cavities in liquid water from purely thermodynamic experimental data. The ultimate objective was to complete a scheme for determining the enthalpies of solute-solvent interaction, from experimental enthalpies of mixing of water with non-ionic organic amphiphiles. Results are given for the analysis of several sets of enthalpy of mixing data, taken from the literature. These results were subjected to a group additivity analysis. The results of these analyses were judged to be consistent with the existence of a substantial enthalpy contribution that is derived from molecular reorganization of the aqueous solvent sheath in addition to the hydrogen bonding between the solute species and solvent water.