Enthalpy of solution of fullerene[60] in some aromatic solvents

Enthalpies of solution (ΔsolnHθ) of fullerene[60] in benzene, toluene, bromobenzene, 1,2-dichlorobenzene and nitrobenzene have been measured in a Precision Solution Calorimeter at 298 K, by using the ampoule breaking technique. The dissolution of C60 in these aromatic organic solvents was observed to be exothermic, with exception of benzene and nitrobenzene, in which the enthalpy is close to zero. From the experimental values of ΔsolnHθ and solubility data of C60 from the literature, ΔsolnGθ and ΔsolnSθ were calculated. We attempted to correlate (ΔsolnHθ) of C60 in these solvents with the solubility, Hildebrand's solubility parameter and polarizability parameter. Thermodynamic data suggest that the process of dissolution of C60 in the studied aromatic solvents is entropically controlled.