Simulation of the molecular and electronic structure of heterofullerenes C 55Y 5 (YSi, Ge, Sn, B, Al, N, P, SiH, GeH, SnH) and their η5- π-complexes with Li by the MNDO method

Abstract

Qualitative estimates of the relative stability of hypothetical heterofullerenes C 55Y 5 (YSi, Ge, Sn, B, Al, N, P, SiH, GeH, SnH) and some η 5- π-complexes LiC 55Y 5 were carried out by the MNDO method. Atoms Y (or groups XH) are assumed to substitute those C atoms in fullerene C 60 which are located at the α-positions of a separated pentagonal face ( pent ∗) of this polyhedral molecule. It is shown that the spin densities in radicals C 55Y 5 (YSiH, GeH, SnH, B, Al, N, P) are localized on the separated pentagon atoms and the Li-pentagonal face (Li- pent ∗) bonds in η 5- π-complexes of these radicals with the Li atom are considerably stronger than Li- pent ∗ bonds in complexes [ η 5- π-LiC 60] + and [ η 5- π-LiC 60] of unsubstituted C 60. In addition, it is established that the Li- pent ∗ bond energies in η 5- π-complexes LiC 55B 5 and LiC 55Al 5 exceed the energy of the Li- pent ∗ bond in the η 5- π-complex LiC 60H 5 studied earlier. In contrast, the energies of similar bonds for YN, P are close to the energy of the Li- pent ∗ bond in the η 5- π-complex LiC 60H 5.