Ce 4f states in CePd2Si2 and CeNi2Si2 investigated by resonant photoemission spectroscopy

Cc 4f electronic states in an antiferromagnetic Kondo compound CePd2Si2 and a strong intermediate-valence compound CeNi2Si2 have been investigated by means of high-resolution Ce 4d-4f resonant photoemission spectroscopy at 12 K. The relative intensity of the f(5/2)(1) to f(7/2)(1) final state in the Cc 4f spectrum for CeNi2Si2 is stronger than the relative intensity for CePd2Si2, indicating that the intensity of Kondo resonance scales the Kondo temperature since the Cc 4f spectrum near the Fermi level dominantly reflects the bulk component. Both Ce 4f spectra have been well fitted by the spectral calculations based on a single impurity Anderson model with consideration of the bulk and surface components. Our present calculation indicates that the model is applicable to the analyses of the Cc 4f spectra of the weakly and strongly hybridized systems.