Relativistic calculations of spin-dependent x-ray-absorption spectra

An efficient interpolative approach is presented for relativistic calculations of polarized x-ray-absorption spectra (XAS) including spin and spin-orbit interactions. The method is based on a spinor-relativistic Dirac-Fock treatment of atomic densities and dipole matrix elements, and a nonrelativistic treatment of propagation using high-order multiple scattering theory. This approach is implemented in an automated code FEFF7 which gives quantitative agreement with experiment for x-ray magnetic circular dichroism of Gd and Fe, and for polarized XAS of Cd, including both $\mathcal{l}\to \mathcal{l}\pm 1$ dipole transitions.