SYSTEMATICS IN THE ELECTRONIC-STRUCTURE OF AMORPHOUS TRANSITION-METAL TIN ALLOYS

Photoemission measurements were performed on in-situ prepared amorphous TM(x)Sn100-x films (TM = Fe, Co, Ni, Pd). Valence band spectroscopy and core level analysis are in contradiction to the charge transfer model, often used to explain the magnetism and binding of transition metal/metalloid alloys. A comparison of valence-band spectra with theoretical density of states (DOS) curves indicates the existence of topological and chemical short-range order. Band structure calculations explain the stability of these alloys as being due to a hybridization pseudo-gap at the Fermi energy. A similar pseudo-gap is also expected within a nearly-free-electron model.