L'ionisation dissociative par impact d'électrons de faible énergie. Distribution d'énergie et énergie d'apparition de fragments doublement chargés de N2 et O2.

Ion energy distributions and threshold energies are measured for the appearance of N2+ from N2. To our knowledge the same data are measured for the first time on O2+ from O2. For both ions a thermal peak is observed in the ion energy distribution having an onset at (61.1+/-0.5) eV and (60.5+/-0.8) eV for the N2+ ion and the O2+ ion respectively. The appearance energy of higher energetic ions is measured and interpreted

L'électronionisation dissociative de l'Ammoniac et de l'Ammoniac-d3. III. Le canal de dissociation conduisant à N+. Conclusions générales relatives à la dissociation de NH3+.

The dissociative ionization of NH3 is investigated in its N+ dissociation channel in the 20-50 eV electron energy range. Both the translational energy distribution and the appearance energies are measured. The kinetic energy-versus-appearance energy plot reveals seven N+ producing processes. Near the onset (22.5-24.0 eV) dissociative autoionization occurs whereas direct dissociative ionization produces N+ in the 24.5-30 eV range. Above 35 eV mainly N+/H+ ion pairs are formed at the expense of doubly ionized states. The dissociative electroionization work on NH3 being completed a review of the results is presented

L'ionisation dissociative du Monoxyde de Carbone.

The dissociative ionization of CO by low energy electron impact into C+ and O (or O-) and O+ and C (or C-) is investigated using ion energy and mass analysis. The kinetic energy distributions are studied as a function of the impinging electron energy. The threshold energies of C+ and O+ are measured as a function of the released kinetic energy. The formation of the products in their ground level and with a small amount of kinetic energy mainly occurs through predissociation. The CO+ electronic states involved in these processes are tentatively identified. New evidences have been found for the importance of dissociative ionization via autoionization