Thermodynamic properties of CF and CF2 from molecular flow effusion and mass spectrometer investigations

The reaction of CF4 and C has been studied in the temperature range 1800–2500 K. Equilibrium data were obtained for species obtained in this temperature range by two techniques: (i) molecular flow effusion and (ii) effusion-mass spectrometry. Heats of formation were calculated from the reaction thermodynamics for the species CF(g), ΔH°f298 K= 58 ± 1 kcal/mol, and CF2(g), ΔH°f298 K=–41.7 ± 0.4 kcal/mol (third law). The S°298 of CF2(g) is 58.9 ± 1.2 cal/deg. mol (second law). Calculations provided thermodynamic limits for the species CF3(g) and C2F2(g).