Electronic and atomic structures of the isomers of endohedral and exohedral fullerene complexes with two lithium atoms

The electronic structures of all the possible isomers of endohedral and exo hedral C-60 fullerene complexes with two lithium atoms are theoretically in vestigated. It is found that the electronic structures of these compounds a re characterized by an impurity filled-level state determining the band gap . The location of the impurity state and, correspondingly, the band gap of the exohedral fullerene complexes depend on the coordination mode and the d istance between the alkali metal ions. A similar dependence is observed for the total energy of the exohedral fullerene complex under investigation. ( C) 2001 MAIK "Nauka/ Interperiodica".