What is "tetracarbon dioxide"

n. (context organic compound English) The linear oxocarbon having four carbon atoms

Tetracarbon dioxide is an oxide of carbon, a chemical compound of carbon and oxygen, with chemical formula CO or O=C=C=C=C=O. It can be regarded as butatriene dione, the double ketone of butatriene — more precisely 1,2,3-butatriene-1,4-dione.

Butatriene dione is the fourth member of the family of linear carbon dioxides O(=C)=O, that includes carbon dioxide CO or O=C=O, ethylene dione CO or O=C=C=O, carbon suboxide CO or O=C=C=C=O, pentacarbon dioxide CO or O=C=C=C=C=C=O, and so on.

The compound was obtained in 1990 by Maier and others, by flash vacuum pyrolysis of cyclic azaketones in a frozen argon matrix. It was also obtained in the same year by Sülzle and Schwartz through impact ionization of ((CH-)(CO)(=O)=) in the gas phase. Although theoretical studies indicated that the even-numbered members of the O(=C)=O family should be inherently unstable, CO is indefinitely stable in the matrix, but is decomposed by light into tricarbon monoxide CO and carbon monoxide CO. It has a triplet ground state.