Reactions of ground-state and metastable O2 + ions with He, O2, N2, and CO2 at thermal energies
Abstract
Evidence is presented that some previous studies of reactions of O2+ ions with various atoms and molecules referred to ion samples composed in part of ions in metastable (1D and/or 1S) states. This finding resolves the 3 orders of magnitude discrepancy between previous experimental and calculated rate coefficients for the O2+(3P)+He charge transfer process. Using a drift tube to distinguish, via arrival time differences, ground-state O2+(3P) and metastable ions, a rate coefficient of (3.5±1.5)×10-11 cm3/sec is obtained for the reaction, in good agreement with that obtained from ab initio theoretical calculations. Previous conclusions concerning reactions of O2+ with O2 and N2, however, remain valid since the difference in reactivity of ground-state and metastable O2+ ions appears to be negligible in this case. The rate coefficient for the reaction O2++CO2 has been determined to be (2±0.5)×10-9 cm3/sec for ions either in the ground-state or in metastable states.
- Publication:
-
Journal of Chemical Physics
- Pub Date:
- January 1981
- DOI:
- 10.1063/1.440834
- Bibcode:
- 1981JChPh..74..305J
- Keywords:
-
- Carbon Dioxide;
- Ground State;
- Helium;
- Ion Atom Interactions;
- Nitrogen;
- Oxygen Ions;
- Atmospheric Chemistry;
- Ionic Reactions;
- Mass Spectroscopy;
- Metastable State;
- Atomic and Molecular Physics