Making atomic carbon :C: - The source of light is the electrical arcing between two carbon rods. Liquid nitrogen cools the reaction vessel. The black substance is soot. This photo was taken in the Laboratory of Professor Phil Shevlin at Auburn University.

Atomic carbon in chemistry is single carbon atom with chemical formula :C: - in effect a dicarbene. An electric arc can melt calcium oxide. ... General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ... General Name, Symbol, Number Nitrogen, N, 7 Chemical series nonmetals Group, Period, Block 15 (VA), 2 , p Density 1. ... Soot, also called lampblack, Pigment Black 7, carbon black or black carbon, is a dark powdery deposit of unburned fuel residues, usually composed mainly of amorphous carbon, that accumulates in chimneys, automobile mufflers and other surfaces exposed to smoke—especially from the combustion of carbon-rich organic fuels in the... Auburn University (AU or Auburn) is a state university located in Auburn, Alabama, in the United States. ... Chemistry (from Persian language کیمیا Kimia and Greek χημεία khÄ“meía[1] meaning alchemy) is the science of matter at the atomic to molecular scale, dealing primarily with collections of atoms, such as gases, molecules, crystals, and metals. ... Atomic redirects here. ... In chemistry a carbene is a short-lived and highly reactive organic molecule with a divalent carbon atom with only six valence electrons and the general formula: R1R2C: . The carbon atom is sp2 hybridised with an empty p-orbital extending above and below a plane containing R1 and R2 and...

The species is very short lived species and is created by passing a large current through two adjacent carbon rods which generates an electric arc. Atomic carbon is generated in the process. Professor Phil Shevlin has done the principle work in the field based at Auburn University in the USA. Auburn University (AU or Auburn) is a state university located in Auburn, Alabama, in the United States. ...

The way this species is made is closely related to the formation of fullerenes C60, the chief difference being that a much lower vacuum is used in atomic carbon formation. Fullerene C540 The Fullerenes are recently-discovered allotropes of carbon. ...

This species has been used to generate "true" carbenes by the abstraction of oxygen atoms from carbonyl groups: In chemistry a carbene is a short-lived and highly reactive organic molecule with a divalent carbon atom with only six valence electrons and the general formula: R1R2C:. The carbon atom is sp2 hybridised with an empty p-orbital extending above and below a plane containing R1 and R2 and... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless (gas) very pale blue (liquid) Atomic mass 15. ... Carbonyl group In organic chemistry, a carbonyl group is a functional group composed of a carbon atom double-bonded to an oxygen atom. ...

R₂C=O + :C: → R₂C: + CO

Carbenes formed in this way will exhibit true carbenic behaviour. Carbenes prepared by other methods such as diazocompounds, might exhibit properties better attributed to the diazocompound used to make the carbene (which mimic carbene behaviour), rather than to the carbene itself. This is important from a mechanistic understanding of true carbene behaviour perspective.

References

• White G. J., Padman R. (1991). "Images of atomic carbon in the interstellar medium". Nature 354: 511 - 513. DOI:10.1038/354511a0. 

• P. B. Shevlin (1972). "Formation of Atomic Carbon in the Decomposition of 5-tetrazoyldiazonium Chloride". J. Amer. Chem. Soc. 94: 1397. DOI:10.1021/ja00759a069. 

• P. B. Shevlin, "The Preparation and Reaction of Atomic Carbon" in Reactive Intermediates, Vol. 1 R. A. Abramovitch Ed. Plenum Press. New York, 1980, p. 1.

• M. J. S. Dewar, D. J. Nelson, P. B. Shevlin, K. A. Biesida (1981). "An Experimental and Theoretical Investigation of the Mechanism of Deoxygenation of Carbonyl Compounds by Atomic Carbon". J. Amer. Chem. Soc. 103: 2802. DOI:10.1021/ja00400a052. 

• K. A. Biesiada and P. B. Shevlin "The Intramolecular Trapping of an Intermediate in the Deoxygenation of a Carbonyl Compound by Atomic Carbon" J. Org. Chem. 1984, 49, 1151. DOI:10.1021/jo00180a047