Buck­minster­fuller­ene-incar-helium

Other names: {60}fuller­ene-incar-helium, iHe(C₆₀-I_h)[5,6]fullerene

He@C₆₀

40/50 uncommon

The fullerenes are a family of carbon allotropes consisting of highly symmetric spheroidal assemblages of carbon atoms, of which C₆₀ (buckminsterfullerene, or "buckyballs") are the archetypal member. Although originally invented so that microorganisms could play soccer ^{[citation needed]}, they also have a variety of other fascinating properties. In particular, they are capable of forming encapsulation complexes called endohedral fullerenes, in which an atom or small molecule is trapped (or, to use the official nomenclature, incarcerated) within the interior of the fullerene, a behaviour which is represented in the chemical formula by the unusual (yet apt) @ symbol. Notable substrates for fullerene encapsulation include molecular CH₄, molecular H₂, and (as depicted here) atomic He.