Excitation of XeF* by reactions of XeF2 with Ar(3P0,2),Kr(3P2) and Xe(3P2)
1977; Elsevier BV; Volume: 46; Issue: 1 Linguagem: Inglês
10.1016/0009-2614(77)85172-5
ISSN1873-4448
AutoresJose E. Velazco, J. H. Kolts, D. W. Setser, J.A. Coxon,
Tópico(s)Catalytic Processes in Materials Science
ResumoThe reactions of the lowest metastable states of Ar, Kr and Xe with XeF2 were studied in a flowing afterglow apparatus; XeF emission (from D2Π12 and B 2Π+ states) was observed in all cases. The total rate constants (cm3 molecule−1 s−1) for XeF* formation were determined as 75 × 10−11 − Xe(3P2);64 × 10−11 − Kr(3P2) and 20 × 10−11 − Ar(3P0,2). The reactions of Ar(3P0,2) and Kr(3P2) with XeF2 also gave ArF* and KrF*, respectively. Analysis of these emissions indicates that at least two different mechanisms are operative: reactive quenching by the ionic—covalent curve-crossing mechanism and excitation transfer. The Ar(3P0,2 + XeF2 reaction is a sufficiently strong source of XeF(D—X) emission that the main features of the XeF(D2Π12 − X2Σ+) system could be photographed and tentative assignments of these vibrational bands are given. The XeF(D → B) emission could not be observed and the ratio of the D—X versus the D—B transition probability must be > 1000 : 1.
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