General rule for the stabilization of fullerene cages encapsulating trimetallic nitride templates
J. M. Campanera, C. Bo, J. M. Poblet
Angew. Chem. Int. Ed. 2005, 44, 7230-7233
Abstract: The bonding in trimetallic nitride template (TNT) endohedral metallofullerenes is widely described by the ionic model Sc3N6+@Ck6-. The ability of the fullerene cage to accept six electrons determines its capacity to encapsulate the TNT unit (see picture). Only free fullerene isomers with a large (LUMO+3)-(LUMO+4) gap can capture and stabilize these four-atom units.