Negative chlorine ion chemistry in the upper stratosphere and its application to an artificially created dense electron cloud

Details Negative chlorine ion chemistry in the upper stratosphere and its application to an artificially created dense electron cloud Negative chlorine ion chemistry in the upper stratosphere and its application to an artificially created dense electron cloud

Mar 1995

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1995angeo..13..296p&link_type=abstract

Annales Geophysicae (ISSN 0992-7689), vol. 13, no. 3, p. 296-304

Physics

1

Anions, Chemical Reactions, Chlorine, Electron Clouds, Ozone Depletion, Photodissociation, Stratosphere, Atmospheric Models, Photodetachment, Photoionization, Solar Radiation

Scientific paper

This paper discusses new potential reactions of chlorine-bearing anions (negative ions) in the upper stratosphere. These reactions are then applied to the negative-ion chemistry following the injection of an electron cloud of very high density, of the order of 10(exp 6)-10(exp 7) e(-)/cu cm, in the 40-45 km region. The idea is to evaluate the recently proposed scheme to mitigate ozone depletion by converting the reactive chlorine atoms at these altitudes into Cl(-) ions which are unreactive towards ozone, i.e., electron scavenging of Cl. We find that the previously neglected photodetachment from Cl(-) is fast. For an overhead sun, this process may have a rate coefficient of 0.08/s when multiple scattering is included. The rate could be even higher, depending on the ground albedo. Switching reaction between Cl(-)-H2O and HCl might lead to the formation of Cl(-)-H2O and Cl(-)-HCl with O atoms could produce ClO(-) and CL2(-). The production of ClO(-) in this manner is significant because Cl(-) having a high photodetachment rate constant would be regenerated in the very likely reactions of ClO(-) with O. When these possibilities are considered, then it is found that the chlorine anions may not be the major ions inside the electron cloud due to the rapid photodetachment from Cl(-). Furthermore, in such a cloud, there may be the hazard that the Cl(-) - Cl(-)- H2O - ClO(-) - Cl(-) cycle amounts to catalytic destruction of two O atoms. Thus, the scheme could be risky if practised in the altitude region where atomic oxygen is an important constituent. Similar conclusions apply even if the ClO(-) species forms ClO3(-) by three-body association with O2, instead of reacting with O. It must be emphasized that the present study is speculative at this time, because none of the relevant reactions have been investigated in the laboratory as yet. The situation at the lower altitudes could be even more complex due to the formation of large cluster ions and the ion-induced aerosol formation. The lower atmospheric situation, therefore, requires much more study.

Affiliated with

Also associated with

No associations

Rating

Negative chlorine ion chemistry in the upper stratosphere and its application to an artificially created dense electron cloud does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Negative chlorine ion chemistry in the upper stratosphere and its application to an artificially created dense electron cloud, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Negative chlorine ion chemistry in the upper stratosphere and its application to an artificially created dense electron cloud will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-884065