Electronic interactions in fullerene spheres

The electron-phonon and Coulomb interactions in ${\mathrm{C}}_{60}$ and larger fullerene spheres are analyzed. The coupling between electrons and intramolecular vibrations give corrections ∼1–10 meV to the electronic energies for ${\mathrm{C}}_{60}$, and scales as ${\mathit{R}}^{\mathrm{-}4}$ in larger molecules, where R is the radius of the fullerene sphere. The energies associated with electrostatic interactions are of order ∼1–4 eV in ${\mathrm{C}}_{60}$ and scale as ${\mathit{R}}^{\mathrm{-}1}$. Charged fullerenes show enhanced electron-phonon coupling, ∼10 meV, which scales as ${\mathit{R}}^{\mathrm{-}2}$. Finally, it is argued that not only ${\mathrm{C}}_{60}^{\mathrm{-}}$, but also ${\mathrm{C}}_{60}^{2\mathrm{-}}$ are highly polarizable molecules. The polarizabilities scale as ${\mathit{R}}^3$ and ${\mathit{R}}^4$, respectively. The role of this large polarizability in mediating intermolecular interactions is also discussed.