2713-09-9Relevant articles and documents
A Shock-Tube, Laser-Schlieren Study of the Dissociation of 1,1,1-Trifluoroethane: An Intrinsic Non-RRKM Process
Kiefer,Katopodis,Santhanam,Srinivasan,Tranter
, p. 2443 - 2450 (2004)
We report a shock-tube, laser-schlieren investigation of the molecular dissociation of the title trifluoroethane, CF3CH3 → CH2CF2 + HF, over very high temperatures, 1600-2400 K, and a wide range of sub-atmospheric pressures, 15-550 Torr. The density gradients are well fit by a simple two-reaction mechanism and accurate dissociation rates obtained. The results are compared with a k∞ calculated from a G3 TS for this molecular elimination, which is a superb fit to the available lower-T data and a reliable extrapolation of k∞ to high temperatures. The derived rate constants show a very deep falloff from, this extrapolation but surprisingly little variation with pressure. This peculiarity is so severe that RRKM calculations dramatically fail to account for the behavior. The dissociation seems to be a clear example of an intrinsic non-RRKM process (nonstatistical dissociation). This conclusion is strongly supported by the observation of double vibrational relaxation at both dissociating and nondissociating temperatures, an unambiguous demonstration of slow IVR. Using a simple model with division into two groups of states, the deep falloff is found to be consistent with a rate-controlling slow IVR, not with low collision efficiency. The model suggests an IVR rate of ～108 s-1 for dissociation energies.
Reactions of photogenerated fluorine atoms with molecules trapped in solid argon 4.* spectroscopic characteristics of β-c2h2f. radicals generated in reactions of mobile f atoms with c2h2 molecules tra
Misochko,Goldschleger,Akimov,Wight
, p. 989 - 995 (2007/10/03)
Reactions of mobile fluorine atoms with C2H2, C2D2, and C2HD molecules in solid argon were studied by ESR and IR spectroscopic techniques. Highly resolved ESR spectra of the stabilized radicals CHF=s
Chlorofluoroacetylene and bromofluoroacetylene by gas phase dehalogenation of 1,1-difluoroethylenes
Runge, Andreas,Sander, Wolfram W.
, p. 5453 - 5456 (2007/10/02)
Chlorofluoroacetylene and bromofluoroacetylene have been prepared by dehalogenation of dichlorodifluoroathylene and dibromodifluoroetnylene, respectively. The products of the direct dehalogenation with alkali metals as well as of the pyrolysis of trimethylstannyl compounds as "stabilized carbenoids" have been isolated in Ar matrices.
