Assessing the solvation mechanism of C60(OH)24 in aqueous solution

Using molecular dynamics simulations, combined with the thermodynamic integration algorithm, we examine the hydration mechanism of C60(OH)24 under ambient conditions. We analyze its structural features, dynamics, and hydration free energy. Our results have been compared with a pristine fullerene aqueous system. Despite the number of hydroxyl groups in the fullerenol, its hydration entropy is rather similar to that calculated for C60. On the other hand, we have calculated a dramatically negative free energy of about −354 kJ/mol for the fullerenol, whereas pure fullerene presents a positive value of about 59 kJ/mol. On this basis, our study indicates that the hydration of C60(OH)24 is guided by an enthalpy-driven process.