Experiments and Simulations of Ion-Enhanced Interfacial Chemistry on Aqueous NaCl Aerosols
10.1126/science.288.5464.301
Crossref journal-article
American Association for the Advancement of Science (AAAS)
Science (221)
Abstract

A combination of experimental, molecular dynamics, and kinetics modeling studies is applied to a system of concentrated aqueous sodium chloride particles suspended in air at room temperature with ozone, irradiated at 254 nanometers to generate hydroxyl radicals. Measurements of the observed gaseous molecular chlorine product are explainable only if reactions at the air-water interface are dominant. Molecular dynamics simulations show the availability of substantial amounts of chloride ions for reaction at the interface, and quantum chemical calculations predict that in the gas phase chloride ions will strongly attract hydroxl radicals. Model extrapolation to the marine boundary layer yields daytime chlorine atom concentrations that are in good agreement with estimates based on field measurements of the decay of selected organics over the Southern Ocean and the North Atlantic. Thus, ion-enhanced interactions with gases at aqueous interfaces may play a more generalized and important role in the chemistry of concentrated inorganic salt solutions than was previously recognized.

Bibliography

Knipping, E. M., Lakin, M. J., Foster, K. L., Jungwirth, P., Tobias, D. J., Gerber, R. B., Dabdub, D., & Finlayson-Pitts, B. J. (2000). Experiments and Simulations of Ion-Enhanced Interfacial Chemistry on Aqueous NaCl Aerosols. Science, 288(5464), 301–306.

Authors 8
  1. E. M. Knipping (first)
  2. M. J. Lakin (additional)
  3. K. L. Foster (additional)
  4. P. Jungwirth (additional)
  5. D. J. Tobias (additional)
  6. R. B. Gerber (additional)
  7. D. Dabdub (additional)
  8. B. J. Finlayson-Pitts (additional)
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  41. The authors are grateful to NSF; the Department of Energy; the UCI Council on Research Computing and Library Resources; and NATO for support of this work. E.K. thanks the Organization of American States for a PRA Fellowship. We thank J. N. Pitts Jr. J. C. Hemminger R. E. Huie D. Margerum R. Sander and P. Davidovits for helpful discussions and E. Chapman C. Berkowitz and C. W. Spicer for providing some of the gas-phase model.
Dates
Type When
Created 23 years ago (July 27, 2002, 5:37 a.m.)
Deposited 1 year, 7 months ago (Jan. 13, 2024, 5:27 a.m.)
Indexed 3 weeks, 4 days ago (Aug. 2, 2025, 12:55 a.m.)
Issued 25 years, 4 months ago (April 14, 2000)
Published 25 years, 4 months ago (April 14, 2000)
Published Print 25 years, 4 months ago (April 14, 2000)
Funders 0

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@article{Knipping_2000, title={Experiments and Simulations of Ion-Enhanced Interfacial Chemistry on Aqueous NaCl Aerosols}, volume={288}, ISSN={1095-9203}, url={http://dx.doi.org/10.1126/science.288.5464.301}, DOI={10.1126/science.288.5464.301}, number={5464}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Knipping, E. M. and Lakin, M. J. and Foster, K. L. and Jungwirth, P. and Tobias, D. J. and Gerber, R. B. and Dabdub, D. and Finlayson-Pitts, B. J.}, year={2000}, month=apr, pages={301–306} }