ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
Negative ion production via electron transfer in collisions between K(nd) Rydberg atoms and CF3Br and CF2Br2 has been investigated over a wide range of of n (10≤n≤70). For both species, the major negative ion observed is Br−, although with CF2Br2, a small Br−2 signal is also detected. Kinematic studies show that Br− production via dissociative attachment is accompanied by sizable translational energy release (∼0.35 eV for CF3Br; ∼0.2 eV for CF2Br2). These studies further show that, despite this large energy release, post-attachment interactions between the product ions are important at intermediate values of n(n(approximately-less-than)20) and suggest that the transient CF3Br−@B| and CF2Br2−* ions initially formed by electron capture have quite different lifetimes against dissociation. Cross sections for free-electron attachment to both species are derived from measurements of rate constants for electron transfer at high n. These cross sections are in reasonable agreement with results obtained in free-electron studies using the threshold photoelectron spectroscopy technique.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.458048
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