Fig. 1: Total ionization cross sections for Ne^*(³P) + Ar, N₂, NH₃ CHEMI.

They are calculated as a function of the collision energy using the Optical potentials formulated in refs. ^7,8,25,34,35. For Ar and N₂ the different reactivity of Ne^*(³P₂) reagent (dashed lines) with respect to that of Ne^*(³P₀) (full lines), with its dependence on the collision energy, is also resolved, which appears to be consistent with the experimental findings⁴⁰. For NH₃ the dependence of the reactivity on the precursor state geometry, opening the formation of NH₃⁺ in its ground (full line) and in its first excited electronic state (dashed line), is shown. θ and φ are the polar angles as defined in the inset of the Figure.