Explanation of the satellite structure observed in the photoemission spectra of coordinated CO

Abstract

We provide a general discussion of the photoemission spectra of transition-metal—carbonyl compounds and CO adsorbed on a transition-metal surface. The screening of the photoexcited hole and the resultant satellite structure due to the excited states of the ion are discussed. The importance of multiplet splittings in the spectra is illustrated, and it is shown that electron correlation must be included to achieve a correct description of the multiplet splitting. This analysis leads to a general interpretation of the core-level spectral region of molecular carbonyls and CO adsorbates.