Dissociation of O2induced by selectiveKhyphen;shell excitation

摘要

Dissociation of O2stimulated by soft xhyphen;ray absorption has been studied by using a monochromatized synchrotron radiation and a timehyphen;ofhyphen;flight mass spectrometer. The parent molecular ion O+2was formed only at 531 eV (excitation of 1srarr;1pgr;g), and a fragment ion O+had the highest intensity in all the energies giving corendash;hole states. The measured timehyphen;ofhyphen;flight spectra were reproduced by a simulation calculation, which provided kinetic energy distributions of O+and O++. The dissociation pathways from the corendash;hole states of O2were discussed using the obtained kinetic energy distribution and ion intensity ratios as well as Auger electron spectra in the literature.