ISSN:
1573-0662
Keywords:
Photochemistry
;
kinetics
;
ozone decomposition
;
iodine atoms
;
IO radicals
;
iodine oxides
;
atmospheric iodine
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Geosciences
Notes:
Abstract The I-atom sensitised decomposition of ozone in air at 1 atm pressure and ambient temperature has been investigated. Iodine atoms were produced by photolysis of I2 using visible light or of CH3I using ultraviolet light. In both cases, the quantum yield for O3 decomposition was 1.25 (±0.11) per I atom. An important role is proposed for the self-reaction of IO radicals leading to higher oxides of iodine, IO+IO(+M)→I2O2(+M)→higher oxides, which predominated over the bimolecular reaction leading to regeneration of I atoms, IO+IO→2I+O2, with k 2a/k 2b≥4. Simple computer modelling calculations indicate that reaction (2a) may be important in determining the fate of photolabile iodine species in the atmosphere. The consequences for the behaviour of radioiodine releases are also discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00130748
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