ICEM-08 Plenary Presenter

Professor Sir Harold W. Kroto

Nobel Laureate in Chemistry 1996

Department of Chemistry and Biochemistry, The Florida State University
Tallahassee, Florida, USA

Harold Kroto received a BSc (Chemistry, 1961) and a PhD (Molecular Spectroscopy, 1964) from the University of Sheffield. After Postdoctoral work at the National Research Council (Ottawa, Canada) and Bell Telephone Laboratories (Murray Hill, NJ USA) he started his academic career at the University of Sussex (Brighton) in 1967. He became a professor in 1985 and a Royal Society Research Professor in 1991. In 1996 he was knighted for his contributions to chemistry and later that year, together with Robert Curl and Richard Smalley (of Rice University, Houston, Texas), received the Nobel Prize for Chemistry for the discovery of C₆₀ Buckminsterfullerene a new form of carbon.

His doctoral research involved high-resolution electronic spectra of free radicals produced by flash photolysis. Among other things such as making the first phosphaalkenes (compounds with carbon phosphorus double bonds), his doctoral studies included research on carbon suboxide, O=C=C=C=O, and this led to a general interest in molecules containing chains of carbon atoms with numerous multiple bonds.

In the 1970s he used microwave spectroscopy to try to discover long, chainlike carbon molecules in the atmospheres of stars and gas clouds. Kroto's group searched for spectral evidence of long, previously undiscovered molecules such as cyanobutadiyne, H-C≡C-C≡C-C≡N and cyanohexatriyne, H-C≡C-C≡C-C≡C-C≡N, and found them from 1975–1978.

In trying to study the vaporization of carbon in order to find out how these carbon chains formed, Kroto and Richard Smalley at Rice University designed a laser-supersonic cluster beam apparatus to simulate the carbon chemistry that occurs in the atmosphere of a carbon star. With this apparatus they were able to vaporize almost any known material and then study the resulting clusters of atoms or molecules. In September 1985 a team including Robert Curl, Jim Heath, Sean O'Brien and Yuan Liu generated clusters of carbon atoms by vaporizing graphite in an atmosphere of helium, showing that carbon stars could indeed produce the carbon molecules chains.

Some of the spectra they obtained from the vaporization corresponded to previously unknown forms of carbon containing even numbers of carbon atoms ranging from 40 to more than 100 atoms. Most of the new carbon molecules had a structure of C₆₀. The researchers recognized that this molecule's atoms are bonded together into a highly symmetrical, hollow structure that resembles a sphere or ball. C₆₀ is a polygon with 60 vertices and 32 faces, 12 of which are pentagons and 20 of which are hexagons (the same geometry as a soccer ball). The researchers chose to name C₆₀ "buckminsterfullerene" in honor of the American architect R. Buckminster Fuller, whose geodesic dome designs have a structure similar to that atom.

The discovery of the unique structure of fullerenes, or buckyballs as this class of carbon compounds came to be known, opened up an entirely new branch of chemistry.

After 1990 when the C₆₀ buckminsterfullerene was finally extracted Kroto and his colleagues Roger Taylor and David Walton explored its synthetic chemistry and materials science implications.

In 1995 he jointly set up the Vega Science Trust a UK educational charity to create high quality science films including lectures, interviews with Nobel Laureates, discussion programmes, careers and teaching resources for TV and Internet Broadcast.

http://www.geoset.info/
http://www.vega.org.uk/
http://www.kroto.info/
http://nobelprize.org/nobel_prizes/chemistry/laureates/1996/kroto-autobio.html

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