Structures and stability of fullerenes, metallofullerenes, and their derivatives

Abstract

This chapter describes general principles in the stability and bonding of empty fullerenes, endohedral fullerenes, and exohedral derivatives of empty fullerenes. First, an overview of the structural properties of empty fullerenes is given. The problem of isomers’ enumeration is described and the origin of the intrinsic steric strain of the fullerenes is discussed in terms of POAV (π-orbital vector analysis) leading to the isolated pentagon rule (IPR). Finally, theoretical studies of the isomers of fullerenes are discussed. In the second part of the chapter, bonding phenomena and molecular structures of endohedral metallofullerenes (EMFs) are reviewed. First, the bonding situation in EMFs is discussed in terms of ionic/covalent dichotomy. Then, the factors determining isomers of EMFs, including those favoring formation of non-IPR cage isomers, are reviewed. In the third part, general principles governing addition of atomic addends and trifluoromethyl radicals to fullerenes are analyzed.