STRUCTURE, TERMINOLOGY, AND HISTORY

This stmcture was first proposed in 1924 (3). The stacking arrangement is ABAB with atoms in alternate planes aligning with each other. Interlayer spacing is 0.3354 nm and interatomic distance within the planes 0.1415 nm. The crystal density is 2.25 g/cm compared to 3.51 g/cm for diamond. 

A rhombohedral form, which occurs in small proportions with the hexagonal form, has a stacking arrangement of ABCABC. Being less stable, it begins to convert to the hexagonal form above 1300°C (4). 

In 1990, a third form of soHd carbon was confirmed and designated TuckniinsterfilUetenes. These 60-carbon (and 78-C) clusters are described as having the shape of a geodesic dome or soccer ball and hence are also known as bucky balls (5). 

Whereas the foregoing ate the forms most commonly found in many appHcations in industry, there ate definitions that ate necessary not only for industrial purposes but also for consistency in the study of carbon science. Since 1975, the International Committee for Characterization and Terminology of Carbon has been working to estabUsh definitions and in 1982 pubHshed its 30 tentative definitions followed by periodic issues of further tentative definitions (10). 

Kirk-Othmer Encyclopedia of Chemical Technology (4th Edition) 

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CARBON - CARBONAND ARTIFICIALGRAPHITE - STRUCTURE TERMINOLOGY AND HISTORY] (Vol 4)... 

Structure, Terminology, and History" under "Carbon (Carbon and Artificial Graphite)" ia ECT3rd ed., Vol. 4, pp. 556—560, byj. C. Long, Union Carbide Corp. 

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