Until 1985, the chemical element Carbon was only known to exist in two forms - diamond and graphite.  This changed when Kroto and co-workers discovered an entirely new form of carbon, which became known as C₆₀ or the fullerene molecule.  (This discovery later led to their award of the 1996 Nobel Prize in Chemistry.) The original discovery of C₆₀ was in the soot produced from the laser ablation of graphite. Since then, other methods of production have been developed. It is also thought that isolated C₆₀ molecules may be found in stars and interstellar media.

The fullerene molecule consists of 60 carbon atoms arranged in pentagons and hexagons, very like in a standard football (soccerball).  It is also known as Buckminster Fullerene due to the resemblance of this shape to the geodesic domes designed and built by the architect R Buckminster Fuller. If you have enabled the running of Java applets in your browser and your browser supports Java1.1, click and drag on the image on the left to rotate it.  If you release your left mouse button whilst dragging in the applet area, the molecule will remain spinning.

It was soon discovered that C₆₀ is not the only ball-like carbon molecule possible (although it is the most stable and the most dominant).   The rugby-ball shaped C₇₀ molecule is another possibility.

It was not until the early 1990s that fullerenes could be synthesised in large enough quantities for significant research in this field to be undertaken. Since then, fullerenes have been prepared in gas and solid phases, in inert gas matrices, in a range of different solutions, as fulleride salts and in polymerised states. Some solids intercalated with alkali metals are superconductors. This means that at temperatures below the transition temperature T_c, a current can flow with no resistance. Even though T_c in the fulleride superconductors is at most 40 K (-233°C) it is only the second-known class of superconductors in which T_c is high enough for potential applications to be a possibility. It is perhaps surprising that some intercalated solids are insulators, i.e. are highly resistant to current flow.

Many of the early experimental results on C₆₀ were unreliable because the samples tended to be small and highly contaminated. However, in the last few years a very large number of reliable experimental results have become available. Despite a high level of activity, many of these results are either unexplained or subject to controversy. Analysis of the data is far from straightforward. One major difficulty is due to the interdisciplinary nature of the subject. The vast majority of experimental investigations are carried out by Chemists, but the processes giving rise to the experimental observations are driven by Physics. We are currently trying to resolve these difficulties by combining the expertise of Chemists and Physicists

In nanotechnology, the potential applications of carbon nanotubes (formed by combining hexagonal rings of carbon atoms only, rather than hexagons and pentagons as in C₆₀) for very small electronic devices are currently the subject of much activity.