Translational energy spectroscopy of NO+ ions formed by charge transfer from Ar+

Translational energy spectroscopy (TES) of NO⁺ ions formed by Ar⁺ charge exchange has been studied. The two features observed in the spectrum are assigned to transitions from the υ″ = 0 and possibly υ″ = 1 and 2 levels of the a³Σ⁺ state to the low vibrational levels of the w³Δ and b′³Σ⁻ states. Comparison with previous TES spectra of NO⁺ formed by electron impact is reported and demonstrates the high selectivity of the charge transfer reaction in populating the first excited state of NO⁺.