Due to the replacement of CFCs by the less harmful HFCs, a huge body of information about the chemistry of these fluorinated compounds has been published and is currently of paramount importance. The radicals produced by these molecules involve mainly the families known as "CF3Ox" and "FCOx". The FCO radical is thus involved in many degradation reactions.

CF3 and FCO radicals are obtained when CF3COF is photolyzed. Both radicals react to give C2F6, CO, CF2O and also regenerate the precursor molecule thus giving a quantum yield of CF3COF disappearance lower than unity (f =0.4).

CF3CF2C(O)F is a suitable source to generate the title radicals allowing to determine whether a longer chain can modify either the photolysis mechanism or the rate constant with respect to the CF3COF.

We performed the photolysis of CF3CF2C(O)F either pure or in the presence of c- C6H12 and (FCO)2 (oxalyl fluoride), following the concentration of the different species by FTIR spectroscopy.

In the photolysis of the pure precursor, the products formed were C4F10, CO and CF2O in accordance with the case of CF3C(O)F.

When enough ciclohexane is added, the radicals formed in the initial step (C2F5 and FCO) are trapped and the recombination reactions between them are suppressed. It is observed that the rate of reactant consumption is faster than without c-C6H12. This suggests that in the photolysis of pure CF3CF2COF, the reaction between C2F5 and FCO radicals plays a role. This was corroborated by the photolysis of CF3CF2C(O)F in the presence of (FCO)2 (i.e. in presence of excess of FCO radicals). Here again, we observed the variation in the rate of disappearance of CF3CF2C(O)F.

The rate constant of the reaction C2F5 + FCO -> CF3CF2COF was obtained through a simulation using both, our experimental data and bibliography data available. The value found is similar, within experimental error, to the rate constant obtained for CF3 and FCO radicals; therefore the length of the chain does not affect the mechanism.