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Part XXIII | ||||
 y worn old Webster gives the following definitions:
Nomenclature: A system of terms used in a particular science ... Terminology: Nomenclature as a field of study ... This apparent overlap in the two nevertheless distinct disciplines is cited to justify my occasional forays into the field of terminology. To wit: A patent recently translated from German had the title (in part) "REINIGUNGSAKTIVE FORMKÖRPER." The English abstract rendered this as "CLEANING ACTION SHAPED BODIES." The invention clearly related to household detergent tablets, but since "Tabletten" were later described as a special case of "Formkörper," the authors were evidently at a loss to differentiate the two terms in English. Furthermore, the abstract itself described the effects of incorporating "herkömmliche Sprengmittel" in the "Formkörper" to improve their "Zerfallsgeschwindigkeit." In English, the abstract teaches us to incorporate "traditional blasting agents" in the "shaped bodies" to improve their "decomposition rate." This would be true enough at high enough temperatures! The unacceptable (to me) title was reworded "MOLDED CAKES WITH CLEANING ACTION." The instructions were modified to advocate incorporating "conventional disintegrants" in the "molded cakes" to increase their "rate of disintegration." Lesson to be learned? Read labels on your own household shelves. And in my case, ask your wife! But above all, be convinced that dictionaries are no substitute for common sense. Nanotechnology—the new buzzword What is nanotechnology? In simple words, it is molecular engineering. The prefix nano-, of course, stands for 10-9, or one (American) billionth (meter implied). The size of a typical small organic molecule is in the nanometer range. The goal of nanotechnology is to fabricate mechanical, electrical, and electronic devices using single molecules as components. We thus find proliferation in the literature of articles with titles such as "Dynamics of a Laser Driven Molecular Motor," and "The Dynamics of Molecular Bearings." The tools needed to emulate conventional machinery on a molecular scale include molecular-scale gears, bearings, wires, shafts, and cams, and the means of assembling them rationally and integrating them with molecular-scale electronic and mechanical control systems. The difficulties of doing these things are perhaps a billion times greater than those encountered in a machine shop. Lathes and milling machines are no longer useful here. Used instead are the techniques of chemistry and physics, including scanning tunneling microscopes. Nanotechnology perhaps gained its greatest impetus in 1985 with the discovery of buckminsterfullerene by Kroto, Curl, and Smalley. Until then, the element carbon had been known in only the two solid, insoluble, refractory forms of graphite and diamond. The chemical formula for either of these forms could be written as C∞, since they both represent infinite networks of interlinked carbon atoms. But when Kroto, Curl, and Smalley vaporized graphite with a laser and analyzed the condensed material, they found distinct, soluble, extremely stable single molecules with the formula C60. Further study showed the molecule to have a spherical structure with the carbon atoms arranged in hexagons and pentagons, much like a soccer ball. Its geometric resemblance also to the geodesic dome structures designed by the architect Buckminster Fuller led the discoverers to coin the name buckminsterfullerene for the new form of carbon. Two illustrations of the new compound are:
Of course C60 is replete with double bonds (unsaturation), which makes it eminently suitable for hydrogenation, halogenation, and substitution. It can also be polymerized into chains of connected spheres:
C60 was by no means the end of the line for the hordes of researchers who quickly entered the fray. C70, C76, C78, C82, C84, C120, and C180 were soon isolated and characterized. Some were found to be spherical while others were distorted. C70, shown below as an example, is ellipsoidal:
The growing group of substances became known collectively as "fullerenes." As chemists tinkered with the new materials they were able to synthesize partially hydrogenated fragments of buckminsterfullerene, as examplified by C36H12:
Because of their open cup-like conformation they became known as "buckybowls" to differentiate them from "buckyballs." Fullerene cages with atoms trapped inside buckyballs were also synthesized:
Cage compounds containing metal atoms were found to have electrical properties of interest to nanotechnologists. Meanwhile, C60 and C70 were found in the naturally-occurring minerals shungite and fulgurite. Geochemists at the University of Washington and the University of Rochester found fullerene cages containing helium and argon atoms in meteorites, thought to have been formed in stars or in collapsing interstellar gas clouds billions of years ago. Fullerene chemistry became of interest in widely diverse fields including cosmology, mechanical engineering, computer science, and of course organic chemistry. The list below is intended to help translators verify some of the terminology (nomenclature?) found in the current technical literature:
Part XXIV will address nanotubes and mechanical components derived from fullerenes, either in the laboratory or by computer simulation. |
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