Absolute cross sections for the VUV optical absorption of Cl₂O in the 6.5-9.7 eV energy range

The VUV photoabsorption spectrum of dichlorine monoxide has been recorded between 6.5 and 9.7 eV photon energies using the UK Daresbury Synchrotron Radiation facility. The spectrum consists of a broad structureless band centred at 7.25 eV followed by several vibrationally resolved high-intensity bands. The 7.25 eV band has been interpreted in terms of the excitation of a dissociative valence excited state while the higher-energy electronic bands (above 7.5 eV) have been classified into several (n = 3, 4) Rydberg states linked with the ionic ground state and its lowest-energy excited states. An analysis of the vibrational progressions associated with the excitation of the various Rydberg states has been completed. © 1997 Elsevier Science B.V.