Fullerens are carbon with spherical structure. Most well-known is C60 ( buckminsture fullerene ). The others are known, too, such as C70, C82 ... or smaller ones ( buckybabies ) such as C20, C28, C36... .

For more information go to :

http://www.susx.ac.uk/Users/kroto/FullereneCentre/

http://www.warwick.ac.uk/staff/M.P.Barrow/fuller.html

http://www.lbl.gov/Science-Articles/Archive/carbon-36-superconductor.html

http://www.msu.edu/~hungerf9/bucky1.html

http://sbchem.sunysb.edu/msl/fullerene.html