Electronic structure and magnetism of rare-earth intermetallic compounds

The electronic structure of R2PdSi3 (R. = Ce, Nd, Tb, Dy, Ho, Er) and HoTX (T = Co, Ni, Rh, Pd, Ag; X = Si, Ge, Sn, Ga) compounds was studied by X-ray and ultraviolet photoemission spectroscopy. For the R2PdSi3 (R. = Nd, Tb-Er) compounds, the valence band is dominated by the multiplet structure of the rare-earth atoms and by the Pd 4d band at E = 4 eV. In these compounds, the density of states at the Fermi level is low and the Ruderman-Kittel-Kasuya-Yosida interaction seems to play a minor role in the magnetic interactions. The valence bands of the HoTX compound are also dominated by the Ho 4f and the transition metal nd (n = 3,4) states. The multiplet structure of the Ho 4f states corresponds to that of the Ho 31 ion for all these compounds. The states at the Fermi level contain contributions from Ho (5d6 s) for T = Ag and from additional nd states of the T element for compounds with T = Co, Ni, Pd and Rh. (C) 2002 Elsevier Science B.V. All rights reserved.