Electron-impact dissociation of oxygen

Abstract

The electron-impact dissociation of O2 to form two oxygen atoms is observed in a crossed beam experiment at electron energies between 13.5 and 198.5 eV. Detection of the correlated dissociation fragments with a time and position sensitive detector permits detection of both ground and excited state fragments, but excludes interference from dissociative ionization products. The observed translational energy releases in the O2 dissociation are consistent with production of O(1D)+O(3P) fragments following electron impact excitation to the B 3Σu−, B′ 3Σu−, and 2 3Πu states, and production of O(3P)+O(3P) fragments from excitation to the (unresolved) c 1Σu−, A′ 3Δu, and A 3Σu+ states. Absolute cross sections for the electron impact dissociation of O2 are measured.