 |
| Titel |
Exploring the atmospheric chemistry of O₂SO₃⁻ and assessing the maximum turnover number of ion-catalysed H₂SO₄ formation |
| VerfasserIn |
N. Bork, T. Kurtén, H. Vehkamäki |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 13, no. 7 ; Nr. 13, no. 7 (2013-04-04), S.3695-3703 |
| Datensatznummer |
250018573
|
| Publikation (Nr.) |
 copernicus.org/acp-13-3695-2013.pdf |
|
|
|
|
|
| Zusammenfassung |
| It has recently been demonstrated that the O2SO3− ion forms in the
atmosphere as a natural consequence of ionizing radiation. Here, we present a
density functional theory-based study of the reactions of O2SO3−
with O3. The most important reactions are (a) oxidation to
O2SO3− and (b) cluster decomposition into SO3,
O2 and O3−. The former reaction is highly exothermic, and the
nascent O2SO3− will rapidly decompose into SO4− and
O2. If the origin of O2SO3− is SO2 oxidation by
O3−, the latter reaction closes a catalytic cycle wherein
SO2 is oxidized to SO3. The relative rate between the two
major sinks for O2SO3− is assessed, thereby providing a measure of
the maximum turnover number of ion-catalysed SO2 oxidation, i.e. how
many SO2 can be oxidized per free electron. The rate ratio between
reactions (a) and (b) is significantly altered by the
presence or absence of a single water molecule, but reaction (b) is
in general much more probable. Although we are unable to assess the overall
importance of this cycle in the real atmosphere due to the unknown influence
of CO2 and NOx, we roughly estimate that ion-induced
catalysis may contribute with several percent of H2SO4 levels in
typical CO2-free and low NOx reaction chambers, e.g. the
CLOUD chamber at CERN. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|