Thermal rate coefficients for reactions involving 2P1/2 and 2P3/2 argon ions and several neutral molecules

Publisher Website
Google Scholar
Abstract
Reactions of argon ions with CO, N2, O2, NO, N2O, CO2, and H2 were investigated at different total pressures with a selected ion‐drift chamber mass spectrometer. The rate data obtained indicate the presence of excited argon ions in addition to argon ions in the ground state. The excited ionic species has been assigned to the 2 P 1/2 metastable state, and these ions were found to undergo collisional quenching as well as reaction. With CO, N2, and O2 the Ar+(2 P 1/2) ions react faster than the Ar+(2 P 3/2) ground state ions and quenching is less significant, while with N2O, CO2, and H2 the Ar+(2 P 1/2) ions are predominantly quenched. The rate coefficients for the ground state argon ions are in reasonable agreement with recent data obtained by flow techniques. NO provides an exception, the reasons for this observation are discussed.