A reassessment of entropy convergence in solvation thermodynamics

Entropy convergence is a well-established phenomenon for the hydration of noble gases, hydrocarbons and n-alcohols, whose theoretical explanation has been associated with cavity creation thermodynamics in water. In the last years, computer simulation studies have cast doubts on the occurrence of entropy convergence on increasing the cavity size. In the present work, classic scaled particle theory calculations are used to show that: (a) entropy convergence occurs in water, but not in carbon tetrachloride for spherical, prolate and oblate spherocylindrical cavities, regardless of their size; (b) its occurrence in water in mainly caused by the special temperature dependence of water density that, in turn, reflects the strength of H-bonds and the plasticity of the 3D H-bonding tetrahedral network.