An XMCD study of the R(4f)-R(5d)T-(3d) interaction in R-T intermetallics

We present an x-ray magnetic circular dichroism (XMCD) study performed at the R L-2 edge in RAl2 and RFe2 series. Regarding the XMCD spectra as made up of two different contributions, XMCDR and XMCDT, have allowed us to find an experimental evidence of the relationship between the XMCD signals and the R(4f)-Fe(3d) and R(4f)-R(4f) interatomic magnetic exchanges that govern the magnetic properties of the R-T intermetallic compounds. We have found that the R dependence of XMCDR and XMCDT signals remarkably mimics the modification of the n(RR) and the n(RT) molecular field coefficients, respectively. These results point out a new experimental method to study the 4f-5d-3d interactions in R-T intermetallics.