The neutral OCCO2, which is predicted to be stable, has not yet been detected experimentally.
The OCCO2 anion is reported to be formed from the co-condensation of laser ablated metal atoms and electrons with CO and CO2 mixture in excess argon.
Attempts were made to produce a neutral OCCO2 of known bond connectivity.
Theoretical calculations indicate that there is a low-lying singlet and a triplet state of neutral OCCO2, but that both of them are unstable with respect to decomposition to ground state CO and CO2, and ground state CO and triplet CO2 respectively.
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Regards
Ramesh