Carbon suboxide

Organic compound with structure O=C=C=C=O

Carbon suboxide, or tricarbon dioxide, is an organic, oxygen-containing chemical compound with formula C3O2 and structure O=C=C=C=O. Its four cumulative double bonds make it a cumulene. It is one of the stable members of the series of linear oxocarbons O=Cn=O, which also includes carbon dioxide and pentacarbon dioxide. Although if carefully purified it can exist at room temperature in the dark without decomposing, it will polymerize under certain conditions.

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