Doubly excited states of molecular nitrogen by scattered electron-ion coincidence measurements

Experimental electron-detachment cross sections for collisions of O2− with N2 molecules in the energy range 50–7000 eV

“…In addition, at 200-eV ion impact energy an average of 10% energy loss to the target may be expected [49] and so, we suggest that the enhancement feature at 200 eV (Fig. 6) is probably due to the role of such double excited states, which by their nature result in either autoionization or neutral dissociation [45]. Such an assumption seems reasonable since we note in Fig.…”

“…Recently, Takahashi et al [45] (and references therein) have reported the relaxation dynamics of doubly excited states as measured with an electron-ion coincidence technique on molecular nitrogen. The generalized oscillator strength distributions of N 2 + and N + showed the mainly autoionizing character of these excited states.…”

“…The structure at 200 eV was interpreted in the light of different processes either through the decay of a temporary negative ion of N 2 −2 g shape resonance formed by charge exchange [24,25,44], reactions involving excited states of O 2 − or the excitation of doubly excited states leading to ionization. Relative ionization cross sections were also reported for N + and N 2 + and the energy behavior related to N + formation (dissociative ionization) is discussed on the basis of double excited states of molecular nitrogen [45][46][47][48].…”