Infrared chemiluminescence from the O + CF2 reaction: part 1.—Kinetics of the emission near 2000 cm–1

Abstract

Time-resolved infrared chemiluminescence has been observed from the reaction of ground-state oxygen atoms with CF₂(X¹A₁) radicals. FTIR measurements were first used to establish the time dependence of the emission spectrum, and kinetic measurements were then carried out using a series of narrowband IR filters. IR emission observed between 1840 and 2350 cm^–1 was assigned to CO₂ formed in the reaction sequence O + CF₂→ FCO + F, O + FCO → CO₂+ F and emitting in the Δv₃=–1 bands. Total IR emission intensities were correlated with CF₂ concentrations as measured by laser-induced fluorescence. Changes in the kinetics and intensities of the IR emission as a function of wavenumber and reagent pressures were consistent with this formation scheme followed by quenching of vibrationally excited CO₂, mainly by collisions with O atoms. An upper limit of 0.06 was estimated for the ratio of vibrationally excited CO to CO₂ produced in the system.