Temperature dependence of the rate constant for the reaction mercapto + nitrogen dioxide

Abstract

at low pressure (~1 Torr) between 221 and 415 K and a negative temperature dependence was observed: kx = (2.9 ± 0.5) X 10"11 exp((240 ± 50)/7") cm3 molecule"1 s"1. The room temperature value for kx from this study is higher than three previous values. Secondary chemistry associated with high H2S concentrations in the earlier studies is believed to contribute to the discrepancies. DS was used to investigate the isotope effect for reaction 1 and no evidence has been observed for a primary.isotope effect, A:(DS + N02) = (7.3 ± 1.1) X 10'11 cm3 molecule"1 s"1, at 299 K. No reaction was observed with 02 and an upper limit of 1.5 X 10"17 cm3 molecule"1 s"1 was assigned to reaction 2.were measured under pseudo-first-order conditions in a discharge flow system coupled to the spectrometer. The results are A:(HSO + N02) = (9.6 ± 2.4) X 10"12 cm3 molecule'1 s"1; fc(HSO + NO) < 1 X 10"15 cm3 molecule"1 s"1; and k(HSO + 02) < 2 X 10"17 cm3 molecule'1 s'1. All measurements were made at low pressures (1-5 Torr) and room temperature (296 ± 3 K). Experiments were also conducted to determine the products of the HSO + NOz reaction. The results show that a species is produced which reacts with 02 to form H02 with a rate coefficient of (3 ± 2) X 10'13 cm3 molecule'1 s'1 which was determined from the rate of H02 formation. We propose that the unidentified intermediate is HS02.

Generation and Decay of Aryl Sulfinyl and Sulfenyl Radicals: A Transient Absorption and Computational Study

“…27 HSO • , for instance, has been proposed to lie along the pathway from HS • to atmospheric H 2 SO 4 by way of reaction with ozone. [28][29][30][31][32] It has also been unambiguously demonstrated that CH 3 SO • is an intermediate in the gas phase photolysis of dimethyl sulfoxide. 33 In this paper we report a solution phase transient absorption study of aryl sulfoxide photolysis designed to characterize directly the proposed arylsulfinyl radical intermediate 1.…”

Environmental effects of large igneous province magmatism: a Siberian perspective

“…This upper limit for k(298 K) is based on the study by Stachnik and Molina [1229] utilizing experiments sensitive to the production of OH. Somewhat higher upper limits of 1.0 × 10 -1-113 17 and 1.5 × 10 -17 were assigned by Friedl et al [472] and Wang et al [1421] respectively from the detection sensitivities for OH detection and SH decay respectively. An even higher upper limit by Black [148], based on the lack of SH decay, may have been complicated by SH regeneration.…”

“…In fact, HSO has been detected as a product by Leu and Smith [808], Bulatov et al [194], Schonle et al [1161], and Wang et al [1421]. The absence of a primary deuterium isotope effect, as observed by Wang et al [1421], coupled with the large magnitude of the rate constant suggests that the (four-center intermediate) channels producing SO + HNO and OH + SNO are of minor importance. No evidence for a three-body combination reaction was found by either Black [148] or Friedl et al [472].…”

“…SH + NO 2 . This recommendation is based on the measurements of Wang et al [1421]. These authors suggest that the lower values of k(298 K) reported by Black [148], Friedl et al [472], and Bulatov et al [194] are due to SH regeneration from the H 2 S source compound.…”

Rotational Energy Transfer of SH(X2Π, v′′=0, J′′=0.5–10.5) by Collision with Ar: Λ‐Doublet Resolved Transition Propensity

“…[1,2] The produced SH has widely attracted studies of its kinetic reactivity with some atmospheric species, [3][4][5][6][7][8][9][10] the related photodissociation dynamics and mechanism, [11][12][13][14][15][16][17] and astrochemical characterization in interstellar space. [18,19] Spectral characterization of SH(X 2 P) radicals yielded the molecular constants and interaction constants for L doublets and hyperfine splitting.…”