In this paper, we report on the design, redox potentials, excited state energies and radical ion pair state energies in electron donor–acceptor conjugates comprising the electron-donating π -extended tetrathia- fulvalene and several electron-accepting fullerenes. To this end, we contrast an empty fullerene, that is, C ₆₀ , with two endohedral metallofullerenes, that is, open-shell La@C ₈₂ and closed-shell La ₂ @C ₈₀ , in terms of charge separation and charge recombination dynamics.