The Scientific Significance Of Buckyball Essay Research

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The Scientific Significance Of Buckyball Essay, Research Paper The Scientific Significance of Buckyballs by ??????????????? Chemistry ??? Section ??? General Chemistry Prof. ????????????? Spring 199? Until the mid-1980?s, elemental carbon was believed only to exhibit two main allotropic forms, diamond and graphite, both of which are covalent-network solids. However, Nobel Prize winning research conducted in the United States and Europe has confirmed the existence of a third previously unknown form of carbon- buckminsterfullerene (C60). The discovery of buckminsterfullerenes, named after Richard Buckminster Fuller, an architect who explored similar shapes in “geodesic” domes made from glass and metal, or buckyballs as they are more commonly referred to, was made at Rice

University, Texas in 1985, during experiments to investigate carbon clusters formed by laser ablation of graphite (Pool 1996). The discovery?s significance was clear from the beginning. “It is hard to identify any other recent finding in chemistry that has stimulated such intense and diverse activity throughout the physical sciences” (Ball 1996). It was clear that the discovery of C60 and the related carbon-cage clusters, collectively known as fullerenes, “would change organic chemistry and materials science” (Ball 1996 p. 561). The conceptual beginning of fullerene science was early as 1966, when David Jones (writing under the pseudonym Daedalus ) speculated about a curved form of graphite similar to geodesic cages (Kroto 1993). However the study of fullerenes was not

fully undertaken until the research conducted by Harold W. Kroto of the University of Sussex in Brighton, United Kingdom and Richard E Smalley and Robert F. Curl Jr. Of the Rice University in Houston. Prior to the discovery, researchers knew of only two naturally occurring forms of carbon: graphite, a soft, black slippery solid in which neighboring carbon atoms are arranged in parallel sheets of hexagons held together by London forces, and diamond: a clear hard solid in which neighboring carbons are grouped into pyramids forming a covalent network (Service 1996). Kroto who was studying the formation of long-chain carbon molecules, called cyanopolyynes, in interstellar space was interested in producing them in a lab. Smalley and Curl had developed a unique machine, that they were

using to study semiconductor clusters, which vaporized small pieces of material using a laser and using a stream of helium gas swept the resulting plasma stream along a high-speed in which molecules and clusters of varying size would form. Working together they began experimenting with graphite. After several days experimenting with and vaporizing graphite, the chemists had found the long chains of carbon atoms that Kroto was looking for. However they had also discovered something else (Pool 1996). Mass spectrometer readings of the vaporized carbon showed some particularly interesting data. The mass spectrum exhibited some peaks corresponding to clusters of carbon atoms with an atomic mass of 720 amu. This molecule consisting of 60 atoms exhibited properties of being extremely

unreactive and unusually stable. But how could this be? “Sheets and pyramids of carbon are only stable when laced together in huge, continuous structures- a diamond for instance. When a carbon structure has as few as 60 atoms, the many dangling bonds at the edges of the sheet or pyramid make the structure highly reactive” (Service 1996). The only explanation for such a molecule would be the structure of the fullerene, a closed carbon-cage molecule containing only pentagonal and hexagonal rings (Fowler 1995). The fullerene hypothesis, as it was known, answered questions concerning the molecules thermodynamic stability. However, the famous soccer ball shape, technically known as a truncated icosahedron, was not fully accepted and many scientist were skeptical. But all doubts