APPLICATION OF THE MOBILE ORDER THEORY TO THE PREDICTION OF AQUEOUS SOLUBILITY OF CHLORINATED BENZENES AND BIPHENYLS

Prediction of the aqueous solubility of solid and liquid polychlorinated biphenyls and benzenes is obtained by means of the mobile order theory. The solubility values are mainly determined by the magnitude of the hydrophobic effect. This effect does not result from the breaking of solvent H-bonded chains in order to separate the solvent molecules to provide a suitably sized cavity for the solute, but from a decrease of the mobile order entropy of each water molecule when the hydrogen-bonded molecules are brought in a large volume consecutively to the addition of the solute. The evolution of the solubility with the chlorine substitution is further explained. The predictive ability of the present model compared to other approaches adapted to predict aqueous solubility as well as its applicability to any given solvent makes this model a very attractive one.