The scientists named the new molecule buckminsterfullerene after the architect. However the scientists still were not sure whether C60 shared the same structure as Fuller’s architectural vision.
Then in 1988 American physicist Donald Huffman and German co-worker Wolfgang Kratschmer looked back on some data they had collected some 6 years previously on carbon soot forms in interstellar space (e.g. in helium or argon; not air), by electrically heating graphite rods. They noticed some odd bumps in the ultra-violet absorption spectrum, at the time they thought it was simply contamination of the soot, but when they looked back they thought could these bumps be a characteristic of buckminsterfullerene?
Just two years later the Huffman and Kratschmer proclaimed they had found a way to make buckminsterfullerene. Whenever someone heats graphite electrically, they would make buckminsterfullerene, but not realise it! By refining their method Huffman and Kratschmer found they could make soot containing 10% C60, contaminated with a smaller amount of a slightly larger molecule C70. News of this discovery spread to Sussex where Kroto and his research students carried out their own experiments, then in 1990 they tried to dissolve the soot in Benzene, and obtained a red solution, there could only be one answer: C60.
Buckminsterfullerene is basically different from the other two types of carbon: diamond and graphite, because it is a molecular form of pure carbon, rather than an infinite structure. However it resembles graphite slightly, as every carbon atom is joined to three others. To make the “football” shaped Buckminsterfullerene, 12 pentagonal faces and 20 hexagonal faces are needed.
As fullerenes have only been discovered recently it doesn’t come as a surprise that there haven’t been many uses found for them yet.
Fullerenes are black solids which are soluble in appropriate solvents to form coloured solutions thanks to their molecular structure. In solution C60 molecules can absorb visible light to form an unstable, excited form of C60, it is better at absorbing light because it is “darker”. This means that the excited form of C60 becomes what is known as an optical limiter. Optical limiters are very significant because they respond instantly to concentrated flashes of light, by becoming darker, so if the excited form of C60 can be utilised, it could be used in protective eyewear for people working with lasers. When a fullerene is "doped" by inserting just the right amount of potassium or caesium into empty spaces within the crystal, it becomes a superconductor - the best organic superconductor known.3 Super conductors are potentially very useful, because the absence of electrical resistance means that, there is no loss of power as heat is not produced when current flows. So an electronic circuit, on a small scale, would not need a cooling system.
Also buckminsterfullerene has a low density compared to its denser relation diamond. It is also a good insulator of electricity, unlike graphite which is a good conductor.
As soon as the rule for composing fullerene cages is known, exceptional carbon structures can be created.
Structure of Buckminsterfullerene:
Top: The structure of the sixty-carbon-atom cluster, called buckminsterfullerene.
Left: The pattern of single and double bonds which allows all of the atoms to form four bonds.
Right: The pattern of hexagons and pentagons in this highly symmetrical shape is the same as that in a soccer ball. 4
In C60 each pentagonal face is surrounded by a band of hexagonal faces, which separates it from the neighbouring pentagonal face. If these ‘bands’ are increased two or threefold, a whole kind of giant fullerenes are created. Below is a diagram of C540 as you can see it is not spherical, it is more icosahedral in shape. 5
If one of these giant fullerenes is stretched, an all carbon zeppelene is created, named after the old fashioned airships called zeppelins. If these zeppelenes are stretched further still, long tubes are produced, these are known as ‘buckytubes’ the idea behind them is fit one inside another to yield molecular pipes. These tubes are the narrowest tube structure ever created, and the finest fibres ever made as well, however these fibres despite their fineness are very strong. Weight for weight buckytubes will be much stronger than the corresponding carbon fibre, currently used in fishing rods.
Bibliography:
1 http://www.chem.wisc.edu/~newtrad/CurrRef/BDGTopic/BDGtext/BDGBucky.html
2 http://naid.sppsr.ucla.edu/expo67/map-docs/images/unitedstates.jpg
3 http://www.imbris.net/~jfromm/bucky/bucky.htm
4 http://metafysica.nl/fuller1.jpg
5 http://upload.wikimedia.org/wikipedia/en/thumb/c/c5/Fullerene_c540.png/250px-Fullerene_c540.png
