ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
Cross sections for the formation of CN(B 2Σ+) in collisions of Ar(3P0,2) and Kr(3P0,2) with BrCN were measured in a crossed beam geometry as a function of the collision energy. An arc-heated metastable rare-gas beam was velocity selected by a time-of-flight method, and the collision energy Ec was varied in the range of 0.7–5.2 eV for Ar(3P0,2) and 1.0–5.2 eV for Kr(3P0,2). The cross sections were found to be proportional to E−mc, with m=0.355±0.008 for Ar(3P0,2) and 0.124±0.010 for Kr(3P0,2). The relative cross sections were normalized against the known absolute cross section for collisional excitation transfer from Ar(3P0,2) to N2. The absolute cross sections thus determined were, for example, 16.0±4.9 A(ring)2 for the Ar(3P0,2)+BrCN system and 42.3±14.8 A(ring)2 for the Kr(3P0,2)+BrCN system at the collision energy of 1.0 eV. The results were explained in terms of the curve-crossing mechanism that an ion-pair [Rg+BrCN−] intermediate state intervenes between the entrance and the exit covalent states.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.461180
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