In traditional chemistry, two forms of carbon oxide are considered stable—carbon dioxide (CO2) and carbon monoxide (CO).
CO2 is a gas on Earth. It is a major component of the atmospheres of Mars and Venus. It also exists as solid ices in the polar regions of Mars and has been detected in the interstellar medium.
CO is common in the outer solar system, such as on objects orbiting in the Kuiper Belt beyond Neptune.
Chemists have turned their attention to more complex carbon oxides, CO3, CO4, CO5 and even CO6, which are highly unstable at room temperature but can be detected in low-temperature ices.
In a Frontiers Article in the Nov. 3, 2008 Chemical Physics Letters, University of Hawaiʻi at Mānoa astrochemist Ralf Kaiser and Florida International University colleague Alexander Mebel present experimental and theoretical studies on the more exotic molecules and suggest directions for further research.
The answers are important not only for understanding solar system chemistry, but in explaining 18O heavy oxygen isotope enrichment in carbon dioxide, a crucial greenhouse gas.
Download the paper (PDF)