Electronic structure of YbTX compounds

The electronic structure of ternary YbTX compounds (T=Au, Pd, Rh, Pt; X=Sn, Bi) was studied by X-ray photoemission spectroscopy (XPS). XPS valence bands were compared with calculations using the tight-binding linear muffin-tin orbital method. The results showed that the valence bands in these compounds were formed mainly by the 4f orbitals of ytterbium and the 4d (5d) orbitals of the transition elements. Analysis of the Yb 4f valence band and Yb 4d core level states clearly indicated the presence of divalent Yb ions in YbAuSn and YbAuBi, and trivalent ions in YbRhSn and YbPtSn. In turn, the Yb ions in YbPdBi exhibited a mixed valence character.