Buckminsterfullerenes

Buckminsterfullerenes Carbon-60

Buckminsterfullerene, C60, the third allotrope of Carbon, was discovered in 1985 by Robert Curl, Harold Kroto and Richard Smalley. Using laser evaporation of graphite they found Cn clusters (where n>20 and even) of which the most common were found to be C60 and C70. For this discovery they were awarded the 1996 Nobel Prize in Chemistry.
Since the discovery of fullerenes over a decade ago, much research has gone into these promising molecules. In 1990 an inexpensive and efficient method to produce fullerenes by the gram (or even kilogram) was discovered by W. Krätchmer and D.R. Huffman. This paved the way for more research into practical applications of the molecules.
Buckyball

Computer generated buckytube image Neon STM buckytube In 1991, Carbon nanotubes were discovered by Sumio Iijima. They were produced by vaporizing carbon graphite with an electric arc under an inert atmosphere. They appered to be made up of a perfect network of hexagonal graphite rolled up onto itself to form a hollow tube. For more information on the production of "buckytubes," follow this link.
To the left can be seen two images of buckytubes, one a simulated representation of the hexagonal graphite tube, the other an image made by a Scanning Tunneling Microscope at Zyvex Corporation.
Buckytubes are extremely strong and flexible; much more so than other forms of Carbon, as shown by the curved buckytube in the image below and to the left.

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Curved Buckytube

Buckytubes can be single walled, or nested inside each other to form multiwalled tubes.
   Among their other intriguing properties is their conductivity. Depending on which direction the sheet of carbon is wrapped to form the tube, it can exhibit either semiconducting or metallic properties. Some scientists are looking into possible applications of these properties in nanocomputers.
Buckytubes of different diameter and helicity are generally described individually by a set of two numbers, e.g. (10,10), (9,0), etc. To help in understanding the notation, here is an explanation by Ralph Merkle, prominent nanotechnology researcher, "start with a point on a graphitic sheet, take an integral number of steps along one crystallographic axis, followed by another (and typically different) integral number of steps along the second crystallographic axis, reaching an endpoint. The straight line connecting the start point and the end point is then defined as the circumference" of the carbon nanotube.   So, basically, the first number is the distance along one axis, and the second number is the distance along a second axis.
   Because of their unique structures, properties and versatility, fullerenes have proven to be ideal for nanotechnology applications.

Other Fullerenes Buckytubes are typically capped, but can also exist as open tubes. They have also been observed with diameters that decrease before the tube ends.
Several other fullerene shapes have been observed, including cone-like fullerenes, fullerene tori, and fullerine spindles. Research into these other fullerenes is underway and their potential appliccations already being investigated.

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