| Autor: |
Simpson, M. J., Tuckett, R. P., Dunn, K. F., Hunniford, C. A., Latimer, C. J., Scully, S. W. J. |
| Předmět: |
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| Zdroj: |
Journal of Chemical Physics; 3/28/2008, Vol. 128 Issue 12, p124315, 10p, 2 Charts, 5 Graphs |
| Abstrakt: |
Ion pair formation, generically described as AB→A++B-, from vacuum-UV photoexcitation of trifluoromethyl sulfur pentafluoride, SF5CF3, has been studied by anion mass spectrometry using synchrotron radiation in the photon energy range of 10–35 eV. The anions F-, F2-, and SFx- (x=1–5) are observed. With the exception of SF5-, the anions observed show a linear dependence of signal with pressure, showing that they arise from ion pair formation. SF5- arises from dissociative electron attachment, following photoionization of SF5CF3 as the source of low-energy electrons. Cross sections for anion production are put on to an absolute scale by calibration of the signal strengths with those of F- from both SF6 and CF4. Quantum yields for anion production from SF5CF3, spanning the range of 10-7–10-4, are obtained using vacuum-UV absorption cross sections. Unlike SF6 and CF4, the quantum yield for F- production from SF5CF3 increases above the onset of photoionization. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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