Anion Mass Spectrometry Study of Ion-Pair Photodissociation of CO₂ in the XUV Energy 19.70-22.24eV

We demonstrate anion mass spectrometry using the Hefei synchrotron radiation source to investigate the ion-pair dissociation processes of molecules. The efficiency curve of the O^- anionic product via ion-pair dissociations of CO₂ is recorded with tunable extreme vacuum ultraviolet photons (energy: 19.70-22.24eV) and compared with the spectrum available in the literature. The possible dynamics of CO₂+hv →CO⁺+O^- in this energy range is discussed.