Electronic spectroscopy of size-selected ionic complexes

Abstract

This article describes spectroscopic investigations of small ionic complexes consisting of a diatomic (N2+) or triatomic (N2O+) core bound to one or more rare-gas atoms (He, Ne, Ar). The experiments involve detecting ionic fragments arising from resonance-enhanced, tuneable laser photodissociation in a tandem mass spectrometer. On the basis of progressions in the low-frequency intracluster vibrations conclusions are drawn concerning ion-neutral potential-energy surfaces in the equilibrium region. Thus the smaller N2+-Hen complexes consist of an almost freely rotating N2+ surrounded by delocalised He atoms, each bound by around 100 cm-1. In contrast N2+-Nen complexes appear to be more stable ..