Superconductivity in Doped Fullerenes

Carbon 60 is a fascinating and arrestingly beautiful molecule. With 12 pentagonal and 20 hexagonal faces symmetrically arrayed in a soccer‐ball‐like structure that belongs to the icosahedral point group $I_h,$ its high symmetry alone invites special attention. The publication in September 1990 of a simple technique for manufacturing and concentrating macroscopic amounts of this new form of carbon (see Donald R. Huffman's article in PHYSICS TODAY, November 1991, page 22) announced to the scientific community that enabling technology had arrived. Macroscopic amounts of ${\mathrm{C}}_{60}$ (and the higher fullerenes, such as ${\mathrm{C}}_{70}$ and ${\mathrm{C}}_{84}$ ) can now be made with anapparatus as simple as an arc furnace powered with an arc welding supply. Accordingly, chemists, physicists and materials scientists have joined forces in an explosion of effort to explore the properties of this unusual molecular building block.