Interaction sites of aNa+ion and a Na atom with aC60molecule

The interactions of the ${\mathrm{Na}}^{+}$ ion and the Na atom with the ${\mathrm{C}}_{60}$ molecule are investigated within the formalism of unrestricted Hartree-Fock theory. Adsorption energies, structural parameters, and electronic energy levels are discussed for four and five sites inside the cage and outside the case, respectively. Possibilities of significant charge transfer from the adatom to the ${\mathrm{C}}_{60}$ molecule and subsequent decreases in the highest occupied molecular orbital–lowest unoccupied molecular orbital gaps are explored. Detailed comparisons with available experimental and theoretical data in the literature are presented.