Trimetallic Nitride Endohedral Fullerenes:Experimental and Theoretical Evidence for the M3N~(6+)?C_(2n)~(6-)model

摘要

The discovery of Sc3N@C_(80)by Dorn and co-workers in 1999 represented the beginning of a new field in the chemistry of endohedral fullerenes.In less than a decade, the family of the metallic nitride endohedral fullerenes(MNEFs)was considerably expanded with the encapsulation of a new Group III metal(Y), lanthanides(Er, Ho, Lu, Tm, Gd, Dy, Tb, Nd, Pr, and Ce)and mixed-metal clusters.Upon increasing the size of the encapsulated metal(from Sc to Gd), the yield of production of MNEFs usually decreases and a distribution of metallofullerenes is obtained, with cages ranging from C_(68)to C_(88).The C_(80)cage, however, remains the most abundant product.Recently, Echegoyen and coworkers reported the preparation of clusterfullerenes, such as Nd3N@C_(2n)(40<=n<=49), and observed the predominant formation of the larger cage C_(88).