Electronic structure of ternary YbMn2X2 (X=Si,Ge) compounds

The electronic structure of YbMn2X2 (X=Si, Ge) compounds with ThCr2Si2-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 YbMn2Ge2, the Yb ion is 2+ while in YbMn2Si2, it is 3+. For both compounds, the Mn 3d states are near the Fermi level. The calculated Mn moments are 1.93 μB for YbMn2Si2 and 2.30 for YbMn2Ge2