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Updated: Aug 9, 2026

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Upper stratospheric photolysis of NaCl and KCl
1Department of Chemistry, University of California, Irvine, California 92717.
Abstract:
Sodium chloride has been postulated to be formed in the stratosphere by the reaction of NaOH with HCl, and an analogous reaction should occur also for KOH, with the formation of KCl. Photodissociation rates have been calculated for both NaCl and KCl using the published ultraviolet absorption cross sections below 300 nm. Both molecules absorb strongly and have photodissociation lifetimes of only a few minutes in the upper stratosphere. Neither molecule is an effective sink for chlorine above an altitude of about 35 km.
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