FTIR-spectroscopic study of reactions of FCO and FC(O)OO radicals in the presence of O-2 and NO2

Steady-state photolysis of oxalylfluoride (FC(O)C(O)F) together with FTIR-spectroscopy has been used to investigate the reactions of FCO and FC(O)OO radicals in the presence of O-2 and NO2. Formation of FCO radicals has been identified as the main photodissociation process of oxalylfluoride at lambda = 254 nm. However, a quantum yield of phi = 0.11 +/- 0.02 was attributed to the direct formation of CF2O and CO in this process. In the presence of O-2, the products of reactions of FC(O)O-x(x = 0, 1, 2) radicals were bis-fluoroformylperoxide (FC(O)OOC(O)F) and bis-fluoroformyltrioxide (FC(O)OOOC(O)F), as well as CF2O, CO and CO2. Addition of NO2 to the reaction system led to the formation of fluoroformylperoxynitrate (FC(O)OONO2). The rate constant for the thermal decomposition of fluoroformylperoxynitrate in the temperature range 275-307 K was measured to be k(T) = 3.5 x 10(16) exp (-13900(-2600)(+1700)/T) s(-1). For bis-fluoroformyltrioxide, a rate constant for thermal decomposition of 6.0 x 10(-4) s(-1) was measured at temperatures around 250 K. The thermal stability of bis-fluoroformyltrioxide and fluoroformylperoxynitrate is discussed in terms of a comparison with the stability of similar molecules.