Detailed balance limits the rate of odd oxygen production in the reaction of vibrationally excited oxygen with O2

1996 ◽  
Vol 23 (10) ◽  
pp. 1083-1086 ◽  
Author(s):  
Darin Latimer ◽  
Patrick McLoughlin ◽  
John Wiesenfeld

2021 ◽  
Author(s):  
Dirk C. van den Bekerom ◽  
Elijah Jans ◽  
Xin Yang ◽  
Anam C. Paul ◽  
Daniil Andrienko ◽  
...  


2021 ◽  
Author(s):  
Valentine Yankovsky ◽  
Ekaterina Vorobeva ◽  
Rada Manuilova ◽  
Irina Mironova

<p>Atmospheric emissions of atomic and molecular oxygen have been observed since the middle of the 19th century. In the last decades, it has been shown that emissions of excited oxygen atom O(<sup>1</sup>D) and molecular oxygen in electronically-vibrationally excited states O<sub>2</sub>(b<sup>1</sup>Σ<sup>+</sup><sub>g</sub>, v) and O<sub>2</sub>(a<sup>1</sup>Δ<sub>g</sub>, v) are related by a unified photochemical mechanism in the mesosphere and lower thermosphere (MLT). The current study is performed in the framework of the state-of-the-art model of ozone and molecular oxygen photodissociation in the daytime MLT. In particular, the study includes a detailed description of the formation mechanism for excited oxygen components in the daytime MLT and presents the comparison of widely used photochemical models. The study also demonstrates new results such as i) new suggestions about possible products of collisional reactions of electronically-vibrationally excited oxygen molecules with atomic oxygen and ii) new estimates of O<sub>2</sub>(b<sup>1</sup>Σ<sup>+</sup><sub>g</sub>, v = 0 – 10) radiative lifetimes which are necessary for solving inverse problems in the lower thermosphere. Moreover, special attention is given to the Barth’s mechanism in order to demonstrate that its contribution to O<sub>2</sub>(b<sup>1</sup>Σ<sup>+</sup><sub>g</sub>, v) and O<sub>2</sub>(a<sup>1</sup>Δ<sub>g</sub>, v) populations is neglectable in daytime conditions regardless of fitting coefficients. In addition, possible applications of the daytime oxygen emissions are presented, e.g., the altitude profiles O(<sup>3</sup>P), O<sub>3</sub> and CO<sub>2</sub> can be retrieved by solving inverse photochemical problems where emissions from electronically vibrationally excited states of O<sub>2</sub> are used as proxies. The funding of V.Y., R.M. and I.M. was partly provided by the Russian Fund for Basic Research (grant RFBR No. 20-05-00450).</p>





2021 ◽  
Author(s):  
Keegan Orr ◽  
Igor Adamovich ◽  
Anam Paul ◽  
Xin Yang ◽  
Elijah Jans ◽  
...  


Nature ◽  
1991 ◽  
Vol 351 (6323) ◽  
pp. 217-219 ◽  
Author(s):  
R. Toumi ◽  
B. J. Kerridge ◽  
J. A. Pyle


From measurements of the absolute concentrations of vibrationally excited oxygen produced in levels v" = 4 to v" = 13, it is concluded that ca . 20 % of the exothermicity of the reaction O( 3 P) + NO 2 → NO + O + 2 ( v" ≤11) (1) appears initially as vibrational energy in oxygen. Vibrationally excited nitric oxide ( v" = 1, 2) is also observed and may be produced in this reaction or in the primary process NO 2 + hv → NO ( v" ≤ 2) + O( 3 P). More highly excited oxygen ( v" ≤ 15), with energy exceeding the exothermicity of the reaction, is produced in reaction (1) when the NO 2 is first excited by radiation above the dissociation limit near 400 nm. The excited NO 2 thus produced can also transfer energy to nitric oxide. NO 2 * + NO( v" = 0) → NO 2 + NO( v" = 1).





1964 ◽  
Vol 40 (2) ◽  
pp. 451-458 ◽  
Author(s):  
Robert V. Fitzsimmons ◽  
Edward J. Bair


2010 ◽  
Vol 10 (20) ◽  
pp. 9953-9964 ◽  
Author(s):  
T. von Clarmann ◽  
F. Hase ◽  
B. Funke ◽  
M. López-Puertas ◽  
J. Orphal ◽  
...  

Abstract. Except for a few reactions involving electronically excited molecular or atomic oxygen or nitrogen, atmospheric chemistry modelling usually assumes that the temperature dependence of reaction rates is characterized by Arrhenius' law involving kinetic temperatures. It is known, however, that in the upper atmosphere the vibrational temperatures may exceed the kinetic temperatures by several hundreds of Kelvins. This excess energy has an impact on the reaction rates. We have used upper atmospheric OH populations and reaction rate coefficients for OH(v=0...9)+O3 and OH(v=0...9)+O to estimate the effective (i.e. population weighted) reaction rates for various atmospheric conditions. We have found that the effective rate coefficient for OH(v=0...9)+O3 can be larger by a factor of up to 1470 than that involving OH in its vibrational ground state only. At altitudes where vibrationally excited states of OH are highly populated, the OH reaction is a minor sink of Ox and O3 compared to other reactions involving, e.g., atomic oxygen. Thus the impact of vibrationally excited OH on the ozone or Ox sink remains small. Among quiescent atmospheres under investigation, the largest while still small (less than 0.1%) effect was found for the polar winter upper stratosphere and mesosphere. The contribution of the reaction of vibrationally excited OH with ozone to the OH sink is largest in the upper polar winter stratosphere (up to 4%), while its effect on the HO2 source is larger in the lower thermosphere (up to 1.5% for polar winter and 2.5% for midlatitude night conditions). For OH(v=0...9)+O the effective rate coefficients are lower by up to 11% than those involving OH in its vibrational ground state. The effects on the odd oxygen sink are negative and can reach −3% (midlatitudinal nighttime lowermost thermosphere), i.e. neglecting vibrational excitation overestimates the odd oxygen sink. The OH sink is overestimated by up to 10%. After a solar proton event, when upper atmospheric OH can be enhanced by an order of magnitude, the excess relative odd oxygen sink by consideration of vibrational excitation in the reaction of OH(v=0...9)+O3 is estimated at up to 0.2%, and the OH sink by OH(v=0...9)+O can be reduced by 12% in the thermosphere by vibrational excitation.



1994 ◽  
Vol 99 (D1) ◽  
pp. 1211 ◽  
Author(s):  
K. O. Patten ◽  
P. S. Connell ◽  
D. E. Kinnison ◽  
D. J. Wuebbles ◽  
T. G. Slanger ◽  
...  


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