First-principles calculation of X-ray dichroic spectra within the full-potential linearized augmented planewave method: An implementation into the Wien2k code

Abstract

X-ray absorption and its dependence on the polarization of light is a powerful tool to investigate the orbital and spin moments of magnetic materials and their orientation relative to crystalline axes. Here, we present a program for the calculation of dichroic spectra from first principles. We have implemented the calculation of X-ray absorption spectra for left and right circularly polarized light into the Wien2k code. In this package, spin-density functional theory is applied in an all-electron scheme that allows to describe both core and valence electrons on the same footing. The matrix elements, which define the dependence of the photo-absorption cross-section on the polarization of light and on the sample magnetization, are computed within the dipole approximation. Results are presented for the L 2 , 3 and M 4 , 5 egdes of CeFe 2 and compared to experiments.