[en] To understand the relationship between the shape of X-ray magnetic circular dichroism (XMCD) and magnetic moments, we calculate V L2, 3-edge XMCD spectra for Mn₂VAl while varying the magnetic moment of an absorbing atom V. We find that XMCD spectra change depending on the magnetic moment of the absorbing atom. We explain these changes based on the magnetic moment dependence of atomic terms, which are components of XMCD. When the overlaps between radial functions and photoelectron wave functions are considered, an atomic term has a value at its energy. The peak positions of the radial integral for up and down spin are different, which leads to multiple peaks of the atomic terms and determines the positive and negative direction of the peak. (author)

[en] Highlights: • The single scattering term of the spin-orbit interaction at scattering sites has a negligible contribution to magnetic EXAFS. • This result substantially differs from the case of x-ray magnetic circular dichroism. • This small contribution comes from the narrow effective range of the spin-orbit interaction. - Abstract: We present an effect of the spin-orbit interaction (SOI) at surrounding atoms on K-edge magnetic extended x-ray absorption fine structure (MEXAFS). A contribution of the SOI to a K-edge MEXAFS spectrum is described by a perturbative way within a multiple scattering (MS) theory. A numerical calculation shows that a photoelectron single scattering by the SOI at surrounding atomic sites has a negligibly small contribution to MEXAFS. Although a negligible contribution of the SOI at surrounding atoms has been attributed to a cancellation of various MS contributions, this small contribution can be understood by the small number of its effective partial wave components, at least within the single scattering approximation. For further detailed analyses of MS with a path expansion method, only the small number of the partial wave components for the SOI is necessary. This leads to faster computations for MEXAFS including the photoelectron scattering by the SOI.

[en] Highlights: • In this work, we have developed a one-step manybody quantum scattering theory to discuss MARX-Raman. • We should point out the differences in the structure factors in the MARPE and MARX-Raman. • Both MARPE and MARX-Raman can provide decisive information on nearby atomic identities and local symmetries. - Abstract: We theoretically study X-ray resonant Raman scattering where the incident photon energy ω_λ is tuned near deep core threshold, and the scattered one ${\omega }_{{\lambda }^{\prime }}$ is tuned so that ${\omega }_{\lambda }-{\omega }_{{\lambda }^{\prime }}$ should be near shallow core threshold: In contrast to ordinary resonant inelastic X-ray scattering (RIXS), they are on different atomic sites. The many-body scattering theory developed by Almbladh and Hedin has been extended to include multi-atom resonant effects. A quite similar formula to multi-atom resonant photoemission (MARPE) was obtained, which cannot be observed in the highly symmetric environment around the shallow core hole sites. In comparison with RIXS, a further non-radiative processes has to be taken into account between the two radiative interactions in the scattering amplitude. The structure factors severely control the possibility to observe MARX-Raman scatterings. They are in the order of R⁻² which is in contrast to the order of R⁻³ for the structure factors in MARPE: R is the distance to the nearby atoms. The condition where we cannot observe MARX-Raman spectra is different from that for MARPE spectra. For the systems with spatial inversion symmetry around the shallow core hole site, we cannot expect to observe the MARX-Raman spectra. For some oxides including heavy metals like PbO and Ag₂O, though they are in low symmetries around oxygens, we cannot expect to observe the MARX-Raman spectra due to the structure factors.