Metal Complexes of Allyl Derivatives of C60 Fullerene: Molecular and Electronic Structure Prediction from Density Functional Calculations.

Abstract

The problem of existence of η3—π-complexes of C60 fullerene with transition metal atoms is discussed. The complexes C60R3Co(CO)3 (R = H, F, Cl, Br), C60H3NiCp, and C60H3Fe(CO)Cp, where C60R3 is an allyl derivative of C60 fullerene, were shown to be sufficiently stable. In these complexes the metal atoms are η3—π-bound to the fullerene cage. In contrast to this, the metal atoms in the C60H3Li and C60H3FeCp complexes are η5—π-coordinated to the carbon cage. Density functional calculations were carried out with the Perdew—Burke—Ernzerhof exchange-correlation potential (PBE). It was concluded that the type of bonding in the complexes of allyl derivatives of C60 fullerene depends on the nature of the species attached. Among the systems studied, the maximum energy of the η3—π-bond was obtained for the C60H3NiCp complex. The results obtained can be useful in the design of synthesis of new fullerene derivatives with the η3—π-coordination of the transition metal atoms to the carbon cage.