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The absolute rate constant for the reaction OH + CH3CCl3 → H2O + CH2CCl3 has been determined by the flash photolysis resonance fluorescence technique from 253 to 363K. The results are used to recommend the Arrhenius expression in units of cm³ molec−1s−1. Use of this equation with atmospheric observational data on methyl chloroform nearly doubles the predicted tropospheric OH reaction sink strength for the removal of important atmospheric gases whose lifetimes are controlled by OH. Comparison of the results reported here with previously reported literature values indicates a strong interference of olefinic impurities on the past investigations.

Flash photolysis of O3 in the Hartley band has been coupled with absorption spectroscopic detection of O2(1Δ, v=0) and resonance fluorescence detection of O(3P) to analyze the fate of O2(1Δ, v?1) in an atmospheric environment. The results indicate a rapid vibrational deactivation under atmospheric conditions. The same analysis permits an estimate of the relative quantum yield of O2(1Δ, v?1) in the photolysis. Similarly, an upper limit for the channel of the O(1D)+O3 reaction yielding O2(1Σ) is derived.

The flash photolysis resonance fluorescence technique has been used to reinvestigate the kinetics of the oxygen atom-oxygen molecule combination reaction. Third-order rate constants for 02, N2, and Ar as deactivant molecules were determined over the temperature range of 219-368 K. The results presented herein are the most extensive data sets available for atmospheric modeling and are used to formulate a recommendation for such purposes. The recommended rate expressions are k p = (1.07 X exp(525/T) cm6/molecule2 sec or hair --(6.3 X 10-34)(T/300)-1.9 cm6/molecule2 sec Comparisons of these results with existing literature data are presented.