Solubility of C₆₀ Fullerene

Abstract

The most recent and comprehensive set of solubility data of C 60 fullerene in various solvents at 298 and 303 K was treated by multivariate stepwise linear regression applied as the linear solvation energy approach. In a few cases where the fullerene formed crystalline solvates, the enthalpy of incongruent melting and the temperature of maximum solubility were used to determine the “hypothetical solubility” of the unsolvated C 60, which was then used in the statistical procedure instead of the solubility of the solvate. The “ideal” solubility of the fullerene was estimated, and the “nonideal” part of the Gibbs energy of solution was then related to solute−solvent interactions. Increasing molar volume and solvent polarity (as measured by the Dimroth−Reichardt “general polarity” parameter, E T (30)) diminished the solubility of C 60, whereas electron pair donation ability and polarizability enhanced solubility.