THE INCLUSION OF CHARGE-TRANSFER TO THE CONDUCTION-BAND IN A CLUSTER MODEL ANALYSIS OF CORE-LEVEL LINE-SHAPES

We have extended the single-impurity cluster model to include the effe cts of charge transfer to the conduction band for the interpretation o f the core level photoemission spectra of highly correlated, small-gap semiconducting and metallic transition metal compounds. The model inc ludes the charge fluctuations between the local transition metal site and the conduction band and has been successfully applied to reinterpr et the spectra of some 3d transition metal chalcogenides, reproducing well the large asymmetry of the main peaks, as well as the other satel lite structures.