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| Titel |
The atmospheric chemistry of sulphuryl fluoride, SO2F2 |
| VerfasserIn |
T. J. Dillon, A. Horowitz, J. N. Crowley |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 8, no. 6 ; Nr. 8, no. 6 (2008-03-13), S.1547-1557 |
| Datensatznummer |
250005923
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| Publikation (Nr.) |
 copernicus.org/acp-8-1547-2008.pdf |
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| Zusammenfassung |
| The atmospheric chemistry of sulphuryl fluoride, SO2F2, was
investigated in a series of laboratory studies. A competitive rate method,
using pulsed laser photolysis (PLP) to generate O(1D) coupled to
detection of OH by laser induced fluorescence (LIF), was used to determine
the overall rate coefficient for the reaction O(1D) + SO2F2 → products (R1) of k1
(220–300 K) = (1.3 ± 0.2) × 10−10 cm3 molecule−1 s−1. Monitoring the O(3P)
product (R1a) enabled the contribution (α) of the physical quenching
process (in which SO2F2 is not consumed) to be determined as
α (225–296 K)=(0.55 ± 0.04). Separate, relative rate
measurements at 298 K provided a rate coefficient for reactive loss of
O(1D), k1b, of (5.8 ± 0.8) × 10−11 cm3 molecule−1 s−1
in good agreement with the value calculated from
(1−α) × k1=(5.9 ± 1.0) × 10−11 cm3 molecule−1 s−1. Upper limits for the rate coefficients
for reaction of SO2F2 with OH (R2, using PLP-LIF), and with
O3 (R3, static reactor) were determined as k2 (294 K)<1 × 10−15 cm3 molecule−1 s−1
and k3 (294 K)<1 × 10−23 cm3 molecule−1 s−1. In experiments using
the wetted-wall flow tube technique, no loss of SO2F2 onto aqueous
surfaces was observed, allowing an upper limit for the uptake coefficient of
γ(pH 2–12)<1 × 10−7 to be determined. These results
indicate that SO2F2 has no significant loss processes in the
troposphere, and a very long stratospheric lifetime. Integrated band
intensities for SO2F2 infrared absorption features between 6 and
19 μm were obtained, and indicate a significant global warming
potential for this molecule. In the course of this work, ambient temperature
rate coefficients for the reactions O(1D) with several important
atmospheric species were determined. The results (in units of
10−10 cm3 molecule−1 s−1,
k(O1D + N2)=(0.33 ± 0.06);
k(O1D + N2O)=(1.47 ± 0.2) and k(O1D + H2O)=(1.94 ± 0.5)
were in good agreement with other recent determinations. |
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