X-ray photoemission spectrum, electronic structure, and magnetism of UCu2Si2

The room temperature X-ray photoemission spectrum of the ferromagnetic compound UCu2Si2 (TC = 100 K) was measured using an Al Kα source. Related theoretical spectra were computed from densities of electronic states obtained in the local density approximation (LDA), the generalized gradient approximation (GGA), and using the GGA + U method. The calculated spectrum is in a good agreement with the experimental one. The spin polarized calculations based on the GGA + U approach as well as GGA/LSDA with orbital polarization (OP) corrections taken into account provide values of the total magnetic moment in reasonable agreement with the experimental values ranging between 1.6 and 2.0 μB/U atom.

► XPS measurements on a single-crystalline sample UCu2Si2.
► Three kinds of band structure calculations using different approaches.
► The calculated spectrum is in a good agreement with the experimental one.
► The spin polarized GGA + U or GGA/LSDA + OP reproduce experimental magnetic moment.