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The kinetics of the fluorine atom abstraction reactions RF+CO→R+FCO (with R=F, CF2(OF)O, CF3O, and SF5O) has been theoretically studied using the density functional theory and ab initio composite models. The derived average activation energies for the reactions of CO with F2 and with CF2(OF)2 of 15.4 kcal mol−1, at 290–320 K, and 23.1 kcal mol−1, at 386–420 K, are in good agreement with the experimental ones. For the F-atom abstraction from the CF3OF and SF5OF molecules, values of 22.7 and 22.5 kcal mol−1 were calculated. Over the 290–320 and 386–420 K temperature ranges, preexponential factors of 1.1 × 10−12 and 4.4 × 10−12 cm3 molecule−1 s−1 were respectively determined for the reactions of CO with F2 and CF2(OF)2 which are 60% larger than the experimental. Values of 2.3 × 10−12 and 1.2 × 10−12 cm3 molecule−1 s−1 were obtained for the reactions corresponding to the SF5OF and CF3OF molecules at 353–383 and 383–423 K, respectively. Unexpectedly, the ωB97X-D, M06-2X and BMK functionals lead to energy barriers much higher than those predicted by other quantum-chemical models. [ABSTRACT FROM AUTHOR]