Triple ionization of CO2 by valence and inner shell photoionization

Spectra of triply ionized CO2 have been obtained from photoionization of the molecule using soft x-ray synchrotron light and an efficient multi-electron coincidence technique. Although all states of the CO2+++ trication are unstable, the ionization energy for formation of molecular ions at a geometry similar to that of the neutral molecule is determined as 74 +/- 0.5 eV. (C) 2011 American Institute of Physics. [doi:10.1063/1.3643121]