Experimental and theoretical study of configuration interaction states of CO+2

Abstract

Configuration interaction states of CO+2 have been observed as satellites in a high resolution photoelectron spectrum of CO2 using an angle resolved electron spectrometer and far UV synchrotron radiation in the 30–55 eV photon energy range. Ten satellites have been identified in the 22–40 eV binding energy region and classified as the result of outer and inner valence ionization processes on the basis of their asymmetry parameter ( β) values. Theoretical calculations of configuration interaction states of CO+2 using an ab-initio SCF-CI method show that three-hole-two-particle excited configurations are necessary to explain the line positions and intensities. The calculated satellite spectrum, corrected for transition moments at 45 and 1254 eV, shows an excellent agreement with experiment and allows assignments of both outer and inner valence satellite lines, with Πg, Πu, Σ+g, and Σ+u symmetries.