Solvation thermodynamics of cyclohexane

The solvation thermodynamics of cyclohexane in pure liquid phase and in water is analyzed by means of the theoretical approach developed by Lee. The sum of the work of cavity creation and the dispersive solute-solvent interaction energy reproduces well the experimental Gibbs energy values over the whole temperature range 5-100degreesC. This implies that the purely structural solvent reorganization is an exactly compensating process in both liquids. The dispersivesolute-solvent interaction energy is larger in magnitude in cyclohexane than in water, whereas the work of cavity creation is larger in water than in cyclohexane. Therefore, both terms contrast the transfer of cyclohexane from pure liquid phase to water, determining its hydrophobicity. This mechanism qualitatively corresponds to that operative in the case of benzene.