Since the discovery of fullerenes in 1985, structural variations on fullerenes have evolved well beyond the individual clusters themselves. Examples include:
- buckyball clusters: smallest member is C 20 (unsaturated version of dodecahedrane) and the most common is C 60;
- nanotubes: hollow tubes of very small dimensions, having single or multiple walls; potential applications in electronics industry;
- megatubes: larger in diameter than nanotubes and prepared with walls of different thickness; potentially used for the transport of a variety of molecules of different sizes;
- polymers: chain, two-dimensional and three-dimensional polymers are formed under high pressure high temperature conditions
- nano"onions": spherical particles based on multiple carbon layers surrounding a buckyball core; proposed for lubricants;
- linked "ball-and-chain" dimers: two buckyballs linked by a carbon chain;
- fullerene rings
