Reaction between HO2 and ClO: Product Formation between 210 and 300 K

Abstract

The products of the gas-phase reaction between H02 and C10 have been measured by matrix-isolation/FTIR spectroscopy at a total pressure of 700 Torr and at 210, 240, 270, and 300 K. HOCl was detected as the dominant product, accounting for 295% of reaction at all temperatures, showing that H 0 1 f C10 -HOCl + 0 2 is the major reaction pathway at high pressures and low temperatures. Evidence was found for ozone formation in this reaction at low temperatures, implying the presence of a second, minor ( 1 5 % ) reaction channel: HOz + C10 -HC1 + 0 3 . No evidence for other product channels was obtained, precluding the formation of long-lived isomers of HC103. The atmospheric implications of a second channel in which O i and HC1 are products are discussed.

High-temperature chemistry of HCl and Cl2

“…The ClO + HO 2 reaction has several product channels, including H-abstraction to form HOCl + O 2 (R25). The Zhu and Lin rate constants are compatible with measurements of the overall rate constant, e.g., [122,123].…”

A model study of the potential role of the reaction BrO + OH in the production of stratospheric HBr

“…--+ HC1 + Oa (R4b) where (R4b) has been shown to be very small at room temperature, i.e. less than 2% [Leck et al, 1980;Leu, 1980;Burrows and Cox., 1981;Finkbeiner et al, 1995]. At the lowest temperature studied (220 K), [Finkbeiner et al, 1995] observe that (R4b) is 5•2 %, at 700 Torr but less than 1% at 2 Tort.…”

“…less than 2% [Leck et al, 1980;Leu, 1980;Burrows and Cox., 1981;Finkbeiner et al, 1995]. At the lowest temperature studied (220 K), [Finkbeiner et al, 1995] observe that (R4b) is 5•2 %, at 700 Torr but less than 1% at 2 Tort. Hence [Finkbeiner et al, 1995] suggest that the rate of reaction (R4b) may be pressure dependent, in which case, over stratospheric pressures, the yield of (R4b) will be less than 5 %.…”

Evaluated kinetic and photochemical data for atmospheric chemistry: Volume III – gas phase reactions of inorganic halogens

“…All of the available data suggest that channel (1) is the dominant, if not sole, pathway over the temperature range of the preferred values With the exception of the matrix-isolation results of Finkbeiner et al (1995) no evidence for channel (2) has been reported. Recent theoretical studies conclude that the contribution of channel (2) (Stevens and Anderson, 1990).…”