Ozone (O3) was synthesized in the condensed phase induced by electron bombardment of multilayer films of molecular oxygen condensed at temperatures below 30 K on metal surfaces. O3 formation was demonstrated by the observation of the asymmetric stretching (ν3) and bending (ν2) normal modes of vibration in a high-resolution electron energy-loss spectroscopy experiment, and by characteristic changes in electron-stimulated desorption of O-. The threshold electron energy for the O3 formation is found at 3.5+/-0.2 eV. It corresponds to the formation of O(3P) associated with O-\(2P\) by dissociative electron attachment at condensed O2, followed by the third body reaction O+O2+O2→O3+O2. Above 5.1 eV bombarding energy, dissociative excitation of the O*2 (c1Σ-u, C3Δu, A3Σ+u, B3Σ-u) states is the main source of atomic oxygen O(3P) or O(1D) involved in the O3 synthesis.
ASJC Scopus subject areas
- General Physics and Astronomy