Thermal and photolytic reactions of gallium and indium atoms (M) and theirdimers M-2 with carbon monoxide in low-temperature matrices: Formation of terminal, bridged, and ionic carbonyl derivatives

Infrared spectroscopy has been used to chart the thermal reactions occurrin g following co-deposition of gallium or indium vapors with carbon monoxide- doped argon at ca. 12 K, as well as the reactions subsequently induced by i rradiating the resulting matrix with UV light (lambda = 200-400 nm). Follow ing deposition, the molecules GaCO, InCO, Ga . GaCO, In . InCO, GaO(mu-CO)G a, Ga(CO)(2), In(CO)(2), and In(CO)(2). In were generated. Under the action of UV light, the Ga/CO system gives rise to the new gallium carbonyl Ga(mu -CO)(2)Ga. Under similar conditions, the complex In+[C2O2](.-) is formed as a result of significant charge transfer between the metal and the CO ligan ds and with the concomitant linking together of two such ligands via a C-C bond. Assignments of the absorption bands are made and the products charact erized on the basis of C-13 substitution and by comparison with the vibrati onal properties of known carbonyl derivatives or with those forecast for no vel species by DFT calculations.