Magnetic and electrical properties of Ce1-xScxFe4Al8 system

At low temperatures the CeFe4Al8 and ScFe4Al8 alloys (tetragonal, ThMn12-ty pe) exhibit a long-range magnetic ordering due to the presence of magnetic moments on the iron sublattice. It is claimed that the Ce atom in CeFe4Al8 is in an intermediate valence state. Here, we address the role of the Sc at om on the behavior of the CeFe4Al8 by alloying it with the isostructural Sc Fe4Al8. Several compositions of the type Ce1-xScxFe4Al8, covering the whole range of mutual substitutions, have been studied by means of X-ray diffrac tion, magnetic and electrical measurements. A decrease of the lattice param eters versus Sc concentration, x, suggests the stabilization of the Ce-atom valence. Yet, due to the dominance of magnetism related to Fe in the magne tic behavior of these alloys, no direct proof of the valence change could b e derived from the magnetic studies. Similar conclusion can be drawn from t he electrical resistivity measurements. (C) 2000 Elsevier Science B.V. All rights reserved.