Kinetics of the F + NO2 + M → FNO2 + M reaction studied by pulse radiolysis combined with time-resolved IR and UV spectroscopy

Abstract

The title reaction was initiated by the pulse radiolys of SF 6 NO 2 gas mixtures, and the formation of FNO 2 was studied by time-resolved infrared spectroscopy employing strong rotational transitions within the ν 1 and ν 4 bands of FNO 2. The pressure dependence of the formation kinetics was studied with SF 6 pressures of 5–1000 mbar at 298 K. Comparative studies were carried out by monitoring the decay kinetics of NO 2 at 445 nm using pressures of 100–1000 mbar at 295 and 341 K. The observed pressure dependence is represented in terms of a fall-off curve with the following values of the limiting high- and low-pressure rate coefficients, k rec,∞ = (2.1 ± 1.0) × 10 10 ( T/300) 0.15 M −1 s −1 and k rec,0 /[ SF 6] = (3.8 ± 1.8) × 10 12 ( T/300) −2.4 M −1 s −1 in the temperature range 200–400 K, and with a broadening factor, F cent = 0.587 × ( T/300) −0.32.