As recently as 1984, carbon was thought to exist in only two solid forms (allotropes). There was graphite, in which the carbon atoms arranged themselves as layered sheets of hexagonally bonded atoms, and there was diamond, in which the carbon atoms formed octahedral structures in which each carbon atom had four nearest neighbors.

Then, in 1985, chemists R. E. Smalley, R. F. Curl, J. R. Heath, and S. O'Brien at Rice University, and H. W. Kroto of the University of Sussex in England observed that a hollow truncated icosahedron, similar in shape to a soccer ball, and consisting of 60 carbon atoms, tends to form spontaneously when carbon vapor condenses. In 1990, physicists D. R. Huffman and L. Lamb of the University of Arizona, working with W. Kratschmer and K. Fostiropoulos of the Max Planck Institute in Germany, discovered a way to make bulk quantities of this C-60 molecule, which investigations using...