Kinetics of the reaction of SH and SD with NO2.
The rate constants for the reactions of NO2 with SH and SD were measured between 250 and 360 K to be 2.8 x 10(-11) exp{(270+/-40)/T(K)} and 2.6x10(-11) exp{(285+/-20)/T(K)} cm3 molecule-1 s-1, respectively. SH(SD) radicals were generated by pulsed laser photolysis of H2S(D2S) or CH3SH and detected via pulsed laser-induced fluorescence. The laser-induced fluorescence excitation spectrum of SH was found to be contaminated by the presence of the SO radical. This contamination is suggested as a possible reason for differences among some of the reported values of k1 in the literature. The title reaction influences the atmospheric lifetime of the SH radical when NO2 is greater than 100 pptv, but the revised value of k1 does not significantly alter our current understanding of SH oxidation in the atmosphere.
Herndon
Scott C
SC
National Oceanic and Atmospheric Administration, Earth System Research Laboratory, and Department of Chemistry and Biochemistry, University of Colorado, Boulder, CO 80309, USA.
Ravishankara
A R
AR