fullerenes

https://doi.org/10.1351/goldbook.F02547
Compounds composed solely of an even number of carbon atoms, which form a @C00769@-like fused-ring @P04724@ with twelve five-membered rings and the rest six-membered rings. The archetypal example is [60]fullerene, where the atoms and bonds delineate a truncated icosahedron. The term has been broadened to include any closed @C00769@ structure consisting entirely of three-coordinate carbon atoms.
Source:
PAC, 1995, 67, 1307. (Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)) on page 1336 [Terms] [Paper]