Mutual neutralization of atomic rare-gas cations (Ne+, Ar+, Kr+, Xe+) with atomic halide anions (Cl−, Br−, I−)
Abstract
We report thermal rate coefficients for 12 reactions of rare gas cations (Ne+, Ar+, Kr+, Xe+) with halide anions (Cl−, Br−, I−), comprising both mutual neutralization (MN) and transfer ionization. No rate coefficients have been previously reported for these reactions; however, the development of the Variable Electron and Neutral Density Attachment Mass Spectrometry technique makes it possible to measure the difference of the rate coefficients for pairs of parallel reactions in a Flowing Afterglow-Langmuir Probe apparatus. Measurements of 18 such combinations of competing reaction pairs yield an over-determined data set from which a consistent set of rate coefficients of the 12 MN reactions can be deduced. Unlike rate coefficients of MN reactions involving at least one polyatomic ion, which vary by at most a factor of ∼3, those of the atom-atom reactions vary by at least a factor 60 depending on the species. It is found that the rate coefficients involving light rare-gas ions are larger than those for the heavier rare-gas ions, but the opposite trend is observed in the progression from Cl− to I−. The largest rate coefficient is 6.5 × 10−8 cm3 s−1 for Ne+ with I−. Rate coefficients for Ar+, Kr+, and Xe+ reacting with Br2− are also reported.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 23, 2014
- Source ID
- 10.1063/1.4862151
Entities
People
- Albert A Viggiano
- Nicholas S Shuman
- Rainer Johnsen
- Thomas M Miller
Organizations
- Air Force Office of Scientific Research
- Air Force Research Laboratory
- University of Pittsburgh