Direct experimental verification of applicability of single-site model for angle integrated photoemission of small T-K concentrated Ce compounds

Abstract

Bulk-sensitive high-resolution Ce 4f spectra have been obtained from 3d --> 4f resonance photoemission measurements on La1-xCexAl2 and La1-xCexRu2 for x = 0.0, 0.04, 1.0. The 4f spectra of low-Kondo-temperature (T-K) (La, Ce)Al-2 are essentially identical except for a slight increase of the Kondo peak with x, which is consistent with a known increase of T-K with x. In contrast, the 4f spectra of high-T-K (La, Ce)Ru-2 show a Kondo-like peak and also a 0.5 eV structure which increases strongly with x. The resonance photon-energy dependences of the two contributions are different and the origin of the 0.5 eV structure is still uncertain. (C) 2002 Elsevier Science B.V. All rights reserved.