Kinetics and mechanisms of the reactions of CH{sub 2}S, CH{sub 3}SO, and CH{sub 3}SS with O{sub 3} at 300 K and low pressures
- National Oceanic and Atmospheric Administration, Boulder, CO (United States)
The reactions of CH{sub 3}S + O{sub 3} {r_arrow} products (1), CH{sub 3}SO + O{sub 3} {r_arrow} products (2), and CH{sub 3}SS + O{sub 3} {r_arrow} (3) were investigated at 300 K in a discharge flow tube reactor coupled to a photoionization mass spectrometer. The measured value of {kappa}{sub 1} is (5.7 {plus_minus} 1.4) x 10{sup {minus}12} cm{sup 3} molecule {sup {minus}1} s{sup {minus}1} Torr He. The authors observed that OH was produced in this reaction or in subsequent steps and that complex branched chain reactions, which generate CH{sub 3}S from its precursor molecule, took place in the flow tube reactor. The authors found that CH{sub 3}SO was a product of reaction 1 and the branching ratio for this channel was 15 {plus_minus} 4%, between 0.7 and 2.2 Torr He, independent of pressure. A preliminary value of {kappa}{sub 2} = (6 {plus_minus} 3) x 10{sup {minus}13} cm{sup {minus}3} molecule{sup {minus}1} s{sup {minus}1} was measured. CH{sub 3}S was not a major product of reaction 2. These results suggest that the reaction with O{sub 3} is a major CH{sub 3}S removal process in the atmosphere. The rate coefficient for the reaction of CH{sub 3}SS with O{sub 3}(3) was measured to be {kappa}{sub 3} = (4.6 {plus_minus} 1.1) x 10{sup {minus}13} cm{sup {minus}3} molecule{sup {minus}1}s{sup {minus}1}. 26 refs., 6 figs., 1 tab.
- OSTI ID:
- 255257
- Journal Information:
- Journal of Physical Chemistry, Journal Name: Journal of Physical Chemistry Journal Issue: 5 Vol. 96; ISSN JPCHAX; ISSN 0022-3654
- Country of Publication:
- United States
- Language:
- English
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