What is "heterofullerene"

n. (context chemistry English) Any compound formally derived from a fullerene by replacing one or more carbon atom by a heteroatom

Heterofullerenes are classes of fullerenes, at least one carbon atom is replaced by another element. Based on spectroscopy, substitutions have been reported with boron ( borafullerenes), nitrogen ( azafullerenes), oxygen, arsenic, germanium, phosphorus, silicon, iron, copper, nickel, rhodium and iridium. Reports on isolated heterofullerenes are limited to those based on nitrogen and oxygen.