Photodissociation Efficiency Spectroscopy Study of the Rydberg Excited Ion-Pair States of Carbon Dioxide

Photodissociation efficiency spectrum of anionic oxygen atom produced via ion-pair dissociations of carbon dioxide is recorded by means of the synchrotron radiation excitation (XUV photon energy 17.40-20.00eV). The present spectrum is assigned as the Rydberg-like excited ion-pair states, i.e., Tanaka-Ogawa and Henning series, ^~C²∑_g⁺ (CO₂⁺) vibrational ground-state and excitation series. Three Rydberg series, npσ_u, npπ_u, and nf_u, converging to ^~C²∑_g⁺ (0,0,0), show the higher cross sections.