Resonant inelastic scattering at intermediate X-ray energies

We describe resonant inelastic X-ray scattering (RMS) experiments and magnetic circular dichroism (MCD) in X-ray fluorescence performed in the 3-5 keV range. The examples chosen are X-ray fluorescence MCD of FeRh and RIXS experiments performed at the L-3 edge of Ce. FeRh is antiferromagnetic at room temperature but has a transition to the ferromagnetic state above 400 K. The Rh MCD signal is confronted to an augmented spherical wave calculation. The experiment confirms the predicted spin polarization of the Rh 4d valence states. The RIXS measurements on Ce compounds and intermetallics address the problem of mixed valency especially in systems where degeneracy with the Fermi level remains small. Examples are taken from the 2p --> (4f5d)(+1) followed by 3d-->2p RIXS for a highly ionic compound CeF3 and for almost gamma-like CeCuSi. (C) 2000 Elsevier Science B.V. All rights reserved.