Electronic states of Sm4As3 and Sm4Bi3 studied with photoemission spectroscopy

Sm4As3 is a Kondo material with a ferromagnetic phase transition at T-c = 160 R. Sm4Bi3 is a valence fluctuation material with a charge ordering below 250 K. Their electronic structures are studied by X-ray photoemission (XPS) and high-resolution 4d-4f resonance photoemission spectroscopy. From the kinetic energy dependence of the spectra. the contribution of the surface component is estimated and the bulk electronic stairs are discussed. Core absorption magnetic circular dichroism (MCD) is measured for Sm4As3 below T-c. 2S(z) is found to be larger than L-z in Sm4As3. (C) 2000 Elsevier Science B.V. All rights reserved.