Theoretical study on the outer- and inner-valence ionization spectra of H2O, H2S and H2Se using the SAC-Cl general-R method

The outer- and inner-valence ionization spectra of the Group VI hydrides H2 O, H2S and H2Se below the double-ionization threshold were studied by the S AC-CI (symmetry-adapted-cluster configuration-interaction) general-R method . The SAC-CI method quite accurately reproduced the experimental spectra of these hydrides and gave detailed characterizations of the shake-up states. Several unknown satellite peaks were predicted. The shake-up state which i ncludes excitations to the Rydberg orbitals was found to be very important for describing the satellite peaks of these hydrides. A detailed inner-vale nce satellite spectrum of H2Se is theoretically proposed prior to any exper imental observation. (C) 2001 American Institute of Physics.