Influence of the channel interaction on the photoabsorption and photoionization spectra of carbon dioxide - art. no. 012512

The integral and the differential photoionization cross sections of carbon dioxide are computed in the random-phase approximation coupled with a K-mat rix based technique. The use of special polynomial spherical Gaussian-type orbitals provides an adequate representation of the electronic continuum. I onization channels originating from occupied valence shell orbitals are con sidered, both in the separated- and interacting-channel approaches up to a photon energy of 100 eV. An accurate account of the effect of the interacti on between the different excitation channels is found to be essential in or der to reproduce the features observed in the experimental photoabsorption and photoionization spectra.