Trifluoromethyl compounds are thought to play a role in the depletion of ozone in the atmosphere. There have been conflicting results from more recent studies on this thinking. In an attempt to bolster more knowledge of these compounds and their impact on the environment, a reaction involving trifluoronitrosomethane (CF3NO) is reported here. CF3NO's vibrational modes have been predicted in previous studies which makes it an ideal molecule to study any photolytic reactions. It is thought to encounter, among other gases, molecular oxygen, in the stratosphere.
The reaction of these two compounds was studied in the lab by condensation of CF3NO(g) and O2(g) and subsequent adsorption of these compounds onto sublimated alkali halide films. Salt film interaction with trifluoronitrosomethane, any products resulting from CF3NO and O2 interaction, and laser photolysis products were analyzed by a Fourier Transform infrared spectrometer. From the infrared spectral data, it appears that after successive photolyses, trifluoronitromethane (CF3NO2), often observed to decompose to various photoproducts, is quenched back to the S0 electronic state due to encounters with oxygen molecules. Secondly, after ultraviolet exposure, an infrared peak, possibly attributable to ozone, was observed on both sodium chloride and sodium bromide films. This peak disappears over the temperature ranges of 35-85 K.
Both rate constants and quantum efficiency calculations were performed. By increasing the temperature over time, spectral data of CF3NO on the NaCl and NaBr films were used to calculate rates of desorption. Rates were not consistent and rates did not fit a linear regression line. Quantum efficiency indicate that CF3NO did not react with coadsorbed O2 after excitation.
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