Abstract |
Carbon from the Allende meteorite is not graphite but carbyne (triply bonded elemental carbon), inasmuch as on heating to 250 degrees to 330 degrees C it releases mainly triply bonded fragments: -(C identical withC)(n),- with n = 1 to 5, and -(C identical withC)(n)-CN, with n = 1 to 3. Although carbynes have been known to form only by condensation of carbon vapor above 2600 K or by explosive shock of > 600 kilobars, it is found that they also form metastably by the reaction 2CO --> CO(2) + C (solid) at 300 degrees to 400 degrees C in the presence of a chromite catalyst. Such low-temperature formation by surface catalysis may be the dominant source of carbynes on the earth and in meteorites, and a major source of interstellar carbynes and cyanopolyacetylenes.
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Authors | R Hayatsu, R G Scott, M H Studier, R S Lewis, E Anders |
Journal | Science (New York, N.Y.)
(Science)
Vol. 209
Issue 4464
Pg. 1515-8
(Sep 26 1980)
ISSN: 0036-8075 [Print] United States |
PMID | 17745960
(Publication Type: Journal Article)
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