Electric Field Induced Dissociation of Molecules in Rydberg-like Highly Vibrationally Excited Ion-Pair States

Abstract

The energetic thresholds for ion-pair photodissociation of diatomic oxygen $[{\mathrm{O}}_{2}+h\ensuremath{\nu}\ensuremath{\rightarrow}{\mathrm{O}}^{+}+{\mathrm{O}}^{\ensuremath{-}}(^{2}P_{3/2},^{2}P_{1/2})]$ were measured using a novel technique. The technique depends on the production and selective detection of highly vibrationally excited ion-pair states which last for at least $5\ensuremath{\mu}\mathrm{s}$ following single photon excitation from the ground electronic state of ${O}_{2}$. These ion-pair states are analogous to Rydberg states, and they may be dissociated by an electric field in a similar manner to the field ionization of high principal quantum number Rydberg states, allowing for their selective detection.