Carbon tetroxide or Oxygen carbonate ''(in its C_2v isomer)'' is a highly unstable oxide of carbon with formula . It was proposed as an intermediate in the O-atom exchange between

carbon dioxide Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transpar ...

() and

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...

() at high temperatures. The C_2v

isomer In chemistry, isomers are molecules or polyatomic ions with identical molecular formulae – that is, same number of atoms of each element – but distinct arrangements of atoms in space. Isomerism is existence or possibility of isomers. Iso ...

, which is 138 kJ mol⁻¹ more stable than the D_2d isomer, was first detected in electron-irradiated ices of

via

infrared spectroscopy Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or function ...

The isovalent carbon tetrasulfide CS₄ is also known from

inert gas An inert gas is a gas that does not readily undergo chemical reactions with other chemical substances and therefore does not readily form chemical compounds. The noble gases often do not react with many substances and were historically referred to ...

matrix. It has D_2d symmetry with the same atomic arrangement as CO₄ (D_2d).

References

Oxocarbons {{inorganic-compound-stub