Electronic structure of ternary YbMn 2X 2 (X=Si,Ge) compounds

Abstract

The electronic structure of YbMn 2X 2 (X=Si, Ge) compounds with ThCr 2Si 2-type of crystal structure has been investigated. XPS measurements were performed using a commercial LHS10 spectrometer. The valence band and the core levels state are analyzed. XPS valence band spectra are compared with the results of ab initio electronic structure calculations using the tight-binding linear muffin-tin orbital method (TB LMTO). Results obtained indicate that in YbMn 2Ge 2, the Yb ion is 2+ while in YbMn 2Si 2, it is 3+. For both compounds, the Mn 3d states are near the Fermi level. The calculated Mn moments are 1.93 μ B for YbMn 2Si 2 and 2.30 for YbMn 2Ge 2.