Journal of Physical Chemistry A, Vol.102, No.40, 7731-7734, 1998
Analysis of the reorientational motion of C-60 in toluene-d(8) : Effects of solute-solvent interactions on rotational times in various solvents
Studies probing the molecular dynamics of C-60 in various environments, and conditions, have been generating a great deal of attention since these investigations have the potential of providing baseline information that might be useful in predicting similar behavior in other members of the fullerene family. We have used C-13 spin-lattice relaxation measurements to analyze the rotational motion of C-60 in toluene-d(8) and have compared these results with data obtained in carbon disulfide and 1,2-dichlorobenzene-d(4). We found that the reorientational times, tau(c), of C-60 in these solvents did not conform to conventional viscosity arguments but were better correlated to the strength of solute-solvent interactions. Consequently, our attempt at theoretically duplicating our correlation times via hydrodynamic-based models proved unsuccessful. Nevertheless, our observations suggest that the success of any future theoretical models will be critically dependent on whether solvent effects are included in the analysis of this type of motion.