CaltechAUTHORS
  A Caltech Library Service

Nitrogen Dioxide Release in the 302 nm Band Photolysis of Spray-Frozen Aqueous Nitrate Solutions. Atmospheric Implications

Dubowski, Yael and Colussi, A. J. and Hoffmann, M. R. (2001) Nitrogen Dioxide Release in the 302 nm Band Photolysis of Spray-Frozen Aqueous Nitrate Solutions. Atmospheric Implications. Journal of Physical Chemistry A, 105 (20). pp. 4928-4932. ISSN 1089-5639. https://resolver.caltech.edu/CaltechAUTHORS:20150623-154758203

Full text is not posted in this repository. Consult Related URLs below.

Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20150623-154758203

Abstract

We quantify the NO_2 fluxes released into the gas phase during the continuous λ ∼ 300 nm photolysis of NO_3^- in submillimeter ice layers produced by freezing aqueous KNO_3 sprays on cold surfaces. Fluxes, F_(NO_2), increase weakly with [NO_3^-] between 5 ≤ [NO_3^-]/mM ≤ 50 and increase markedly with temperature in the range of 268 ≥ T/K ≥ 248. We found that F_(NO_2), the photostationary concentration of NO_2^- (another primary photoproduct), and the quantum yield of 2-nitrobenzaldehyde in situ photoisomerization are nearly independent of ice layer thickness d within 80 ≤ d/μm ≤ 400. We infer that radiation is uniformly absorbed over the depth of the ice layers, where NO_3^- is photodecomposed into NO_2 (+ OH) and NO_2^- (+ O), but that only the NO_2 produced on the uppermost region is able to escape into the gas phase. The remainder is trapped and further photolyzed into NO. We obtain φ_(NO_2^−) ∼ 4.8 × 10^(-3) at 263 K, i.e., about the quantum yield of nitrite formation in neutral NO_3^- aqueous solutions, and an apparent quantum yield of NO2 release φ‘_(NO_2) ∼ 1.3 × 10^(-3) that is about a factor of 5 smaller than solution φ_(OH) data extrapolated to 263 K. These results suggest that NO_3^- photolysis in ice takes place in a liquidlike environment and that actual φ‘_(NO_2) values may depend on the morphology of ice deposits. Present φ‘_(NO_2) data, in conjunction with snow albedo and absorptivity data, lead to F_(NO_2) values in essential agreement with recent measurements in Antarctic snow under solar illumination.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://dx.doi.org/10.1021/jp0042009DOIArticle
http://pubs.acs.org/doi/abs/10.1021/jp0042009PublisherArticle
ORCID:
AuthorORCID
Colussi, A. J.0000-0002-3400-4101
Hoffmann, M. R.0000-0002-0432-6564
Additional Information:© 2001 American Chemical Society. Received: November 14, 2000; In Final Form: March 7, 2001. We are grateful for research funds provided by the foundation Environmental Now.
Funders:
Funding AgencyGrant Number
Environmental NowUNSPECIFIED
Issue or Number:20
Record Number:CaltechAUTHORS:20150623-154758203
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20150623-154758203
Official Citation:Nitrogen Dioxide Release in the 302 nm Band Photolysis of Spray-Frozen Aqueous Nitrate Solutions. Atmospheric Implications Yael Dubowski, A. J. Colussi, and M. R. Hoffmann The Journal of Physical Chemistry A 2001 105 (20), 4928-4932 DOI: 10.1021/jp0042009
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:58485
Collection:CaltechAUTHORS
Deposited By: George Porter
Deposited On:28 Jul 2015 20:15
Last Modified:03 Oct 2019 08:36

Repository Staff Only: item control page