Vibrational Energy Transfer and Relaxation in O₂and H₂O

Abstract

Near-resonant vibrational energy exchange between oxygen and water molecules is an important process in the Earth's atmosphere, combustion chemistry, and the chemical oxygen iodine laser (COIL). The reactions in question are (1) O2(1) + O2(0) --> O2(0) + O2(0); (2) O2(1) + H2O(000) --> O2(0) + H2O(000); (3) O2(1) + H2O(000) <--> O2(0) + H2O(010); (4) H2O(010) + H2O(000) --> H2O(000) + H2O(000); and (5) H2O(010) + O2(0) --> H2O(000) + O2(0). Reanalysis of the data available in the chemical kinetics literature provides reliable values for rate coefficients for reactions 1 and 4 and strong evidence that reactions 2 and 5 are slow in comparison with reaction 3. Analytical solution of the chemical rate equations shows that previous attempts to measure the rate of reaction 3 are unreliable unless the water mole fraction is higher than 1%. Reanalysis of data from the only experiment satisfying this constraint provides a rate coefficient of (5.5 +/- 0.4) x 10(-13) cm3/s at room temperature, between the values favored by the atmospheric and laser modeling communities.

Mode transition and plasma characteristics of nanosecond pulse gas–liquid discharge: Effect of grounding configuration

“…Gas heating processes can be achieved via the vibrational‐to‐translational (V–T) energy relaxation process . Though the V–T relaxation process is accelerated by H 2 O, the time scale of V–T relaxation (1–100 μs) is still much longer than the streamer phase duration time (~60 ns) . Therefore, the V–T energy transfer is not the main pathway of gas heating in the streamer discharge when the indirect grounding configuration is used, and the gas heating processes are due to the electron‐impact dissociation of N 2 and electron‐ion recombination processes .…”

“…[36] Though the V-T relaxation process is accelerated by H 2 O, the time scale of V-T relaxation (1-100 μs) is still much longer than the streamer phase duration time (~60 ns). [37,38] Therefore, the V-T energy transfer is not the main pathway of gas heating in the streamer discharge when the indirect grounding configuration is used, and the gas heating processes are due to the electron-impact dissociation of N 2 and electron-ion recombination processes. [39] In the direct grounding configuration, more electrons are generated, making the electron-impact dissociation of N 2 and electron-ion recombination processes more intense, then resulting in a high gas temperature.…”

Model of electronic-vibrational kinetics of the O3and O2photolysis products in the middle atmosphere: applications to water vapour retrievals from SABER/TIMED 6.3 μm radiance measurements

“…where K = 1 × 10 -20 + 7.7 × 10 -11 exp(−115/T 1/3 ) + 5.3 × 10 -7 exp(−199/T 1/3 ) (Huestis 2006). Strong dependence of this rate constant on temperature in comparison with commonly used rate constant K = 4.2 × 10 -19 (T/300) 0.5 (López-Puertas et al 1995) leads to a 2.0-2.5 times increase of the first excited vibrational level population, O 2 (X 3 − g , v = 1), near the mesopause and to its 1.5-2.0 times decrease near the stratopause.…”

Cross Sections and Reaction Rates for Comparative Planetary Aeronomy

“…The form of this expression is a generalization of the Landau and Teller (1936) representation of vibrational and rotational relaxation (Huestis 2006a(Huestis , 2008. The overall rate of electronic relaxation of O 2 (a 1 g , v = 0) in Reaction (22) has been measured near room temperature in a number of investigations (Sander et al 2006), in liquid oxygen (Huestis et al 1974;Protz and Maier 1980;Faltermeier et al 1981;Wild et al 1982Wild et al , 1984, and more recently in gaseous oxygen between 100 and 500 K (Billingham and Borrell 1986;Chatelet et al 1986;Seidl et al 1991).…”

“…The rate of vibrational energy exchange has been of interest to atmospheric scientists, combustion modelers, and developers of chemical lasers. It has been recently inferred from analysis of unpublished laser-based laboratory experiments (Huestis 2006a). The reactions in question are …”