Positive ion-negative ion coincidence spectroscopy of CO 2 for observation of doubly excited rydberg states

Abstract

Positive ion-negative ion coincidence (PINICO) spectroscopy of CO 2 has been studied by using synchrotron radiation to observe highly excited states lying in the 25–37 eV excitation energy range. Several resonance-like peaks are observed in the photodissociation efficiency curves for the two ion-pair formation processes, CO 2 → O −+C ++O and CO 2 → O −+CO +. Some of the peaks are tentatively assigned to doubly excited Rydberg states of CO 2 converging to CO 2 + satellite states.