Time-resolved IR studies of gas-phase photochemistry of Co(CO)3NO
Abstract
Time-resolved IR spectroscopy has been used to study the gas-phase photochemistry of Co(CO)3NO at 355 and 266 nm. The major IR spectra observed have been assigned. 355 nm photolysis of Co(CO)3NO leads to the predominant formation of Co(CO)3 and Co(CO)2No via elimination of NO and CO, respectively. The branching ratio for loss of NO vs. loss of CO was ca. 3/2, favouring scission of the Co—NO bond. 266 nm photolysis resulted in the formation of Co(CO)2 and NO-retaining products. The overall branching ratio for NO-depleted vs. NO-retaining products was ca. 2. The implication behind these branching ratios is discussed with regard to the photodissociation mechanism. Co(CO)n reacts with CO forming Co(CO)n+1 with rate constants of (3.4 ± 0.5)× 10–11 and (3.5 ± 0.6)× 10–11 cm3 molecule–1 s–1, for n= 3 and 2, respectively.