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A first-principles theory of resonant magnetic scattering of x rays is presented. The scattering amplitudes are calculated using a standard time-dependent perturbation theory to second order in the electron-photon interaction vertex. In order to calculate the cross section reliably an accurate description of the electronic states in the material under investigation is required and this is provided by the density functional theory (DFT) employing the Local Spin Density Approximation combined with the self-interaction corrections (SIC-LSD). The magnetic x-ray resonant scattering (MXRS) theory has been implemented in the framework of the relativistic spin-polarized LMTO-ASA band structure calculation method. The theory is illustrated with an application to ferromagnetic praseodymium. It is shown that the theory quantitatively reproduces the dependence on the spin and orbital magnetic moments originally predicted qualitatively (Blume, J. Appl. Phys, {bf 57}, 3615 (1985)) and yields results that can be compared directly with experiment.
The electronic structures of several actinide solid systems are calculated using the self-interaction corrected local spin density approximation. Within this scheme the $5f$ electron manifold is considered to consist of both localized and delocalized
We introduce a first principles approach to determine the strength of the electronic correlations based on the fully self consistent GW approximation. The approach provides a seamless interface with dynamical mean field theory, and gives good results
X-ray absorption spectroscopy measurements in Pr0.5Ca0.5CoO3 were performed at the Pr M4,5, Pr L3, and Ca L2,3 absorption edges as a function of temperature below 300 K. Ca spectra show no changes down to 10 K while a noticeable thermally dependent e
In this work we present a model for the determination of the interaction energy for triplet and singlet states in atoms with incomplete filled shells. Our model includes the modification of the Coulombs law by the interaction between the magnetic mom
A well-known property of aromatic molecules is their highly anisotropic response to the presence of an external magnetic field: the component of their magnetic susceptibility parallel to the field is generally much larger than the remaining in-plane