Kinetic energy dependence of Al++O2→AlO++O

Publisher Website
Google Scholar
Abstract
The endothermic reaction of Al+ with O2 is studied using a guided ion‐beam apparatus. The reaction cross section is measured as a function of kinetic energy from 0 to 20 eV. The threshold energy for the reaction, E0, is determined from an empirical model to be 3.64±0.04 eV. Phase space calculations of the cross section performed with E0 as the only adjustable parameter yield a similar result, E0=3.60±0.02 eV, and predict the absolute magnitude of the reaction cross section within experimental error. We conservatively quote the threshold energy as 3.62±0.12 eV which is somewhat higher than the thermodynamic threshold calculated using literature thermochemistry, 3.40±0.16 eV. This may indicate that a slight barrier to the reaction exists, or that AlO+ is produced in an excited state, or that the literature thermochemistry needs revision. Our results suggest D00 (AlO+)≥1.50±0.12 eV and I.P.(AlO)≤9.75±0.13 eV.