Laser-ablated V and Ti atoms react with CO2 molecules to give primarily the insertion products, OMCO and O2M(CO)(2), which have been isolated in a solid argon matrix. Photoisomerization of OMCO molecules to form the side-bonded OM-(eta(2)-CO) isomers and photoionization to give the OMCO+ and OMOC+ cations proceed upon mercury are photolysis. The product absorptions were identified by isotopic substitution and density functional calculations of isotopic frequencies.