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Subject - Organic Chemistry

In addition to diamond and graphite, fullerenes are another allotrope of carbon. In 1985, chemists Robert F. Curl (USA), Harold W. Kroto (GB) and Richard E. Smalley (USA) discovered the formation of fullerene C60 by heating and evaporating graphite with a laser. In 1996, they were awarded the Nobel Prize in Chemistry for their discovery.

Structure of C60 fullerene

Fullerenes are hollow spheres which consist of pentagonal and hexagonal rings. The name was a homage to the American architect Richard Buckminster Fuller whose geodesic domes they resemble. Stable fullerenes always contain 12 five-membered rings which are surrounded on all sides by six-membered rings. The C60 modification with 12 five- and 20 six-membered rings meets these criteria as the smallest representative. The next stable member of the fullerenes, C70, differs from C60 by five additional C2 building blocks giving the molecule a lengthy look.

Only in 1990, research groups of W. Krätschmer in Germany and D.R. Huffman in USA developed a process for the preparation of larger amounts of fullerenes. Practical or technical applications of fullerenes do not exist. Nanotubes in which the carbon atoms are aligned in six-membered rings are modifications of fullerenes. A large number of applications has been developed or is being discussed for nanotubes. These include hydrogen storage, flat screens, composite materials, catalysts, membranes, and quantum wires.

See also: diamond , graphite , carbon