Elastic and inelastic scattering of Li⁺ions by rare gases (Ne, Ar, Kr, Xe)

Excitation mechanisms in moderate-energyNa+-Ar collisions

“…One can then evaluate the excitedstate potential for reaction (8), as well as the ground-state potential by the fitting of the DCS o (e)ii, . According to Barat et al [11],the electronic transition in this colliding system takes place through the noncrossing interaction rather than the crossing interaction. However, the experimental results suggest that the transition occurs at a localized internuclear distance.…”

“…For symmetric and quasisymmetric systems, excitation probability is especially high even at lower collision energies [1 -8], while the probability for asymmetric systems is low [9 -13], except for Li+-Ne [11] and He-rare gas systems [14]. Another remarkable feature in the inelastic collisions of closed-shell particles is the fact that excitation into a doubly excited state lying at a higher energy is observed with a high probability and with the threshold energy being almost the same as that for one-electron excitation.…”

“…For the Na+-Ar collisions, an energy-loss spectrum of the Na+ ions scattered at E&,b = 5 keV and 8=4.5 [10],and an energy spectrum of electrons ejected from autoionizing states of Ar atoms at E&,b =15 keV [27] have been briefly reported, but, to our knowledge, no investigation on the excitation mechanisms in moderate-energy collisions has been reported up to now. Differential scattering of Li+ ions from rare gases has already been studied at energies of E&,b & 500 eV and the smaller angles 0&30', and the excitation mechanisms have been discussed in detail [11]. In order to compare with the results of Na+-Ar, differential scattering in the eV in this work.…”

Charge-overlap effect on the electronic transitions in moderate-energy collisions between closed-shell particles with rare-gas structure

“…͑0.53 Å͒ between the promoted 3d MO correlating to the Ne 2 p atomic orbital ͑AO͒ and the MO's correlating to the excited-state AO's, which have been evaluated with the ab initio calculations. 25 However, the potential crossings in Fig. 3͑a͒ are somewhat different from the diabatic correlation diagram of the states estimated with the electron-promotion model 11 ͑see Fig.…”

“…8 The ab initio calculations of the potentials for Li ϩ -Ar suggest that the electronic transitions observed in the collisions at large and intermediate distances are due to the noncrossing interactions. 8,25 Nevertheless, in Fig. 3͑b͒ potential curves 2 and 3 cross curve 1 at R c ϭ0.86 and 0.75 Å (Vϭ40 and 63 eV͒, respectively.…”