XMCD at the Co K-edge in RCo2 intermetallics:: influence of the rare earths

X-ray magnetic circular dichroism (XMCD) studies have been performed at the Co K edge in RCo2 intermetallics (R = Nd, Tb and Ho). A drastic evolution in the structure of XMCD spectra is observed between Co metal and alloys. The RCo2 dichroic spectra exhibit a three-peaks structure: one negative in the middle of the positive ones. Sizeable changes in the intensities are observed when switching the rare earth. A huge signal, approximate to 0.6%, is measured on HoCo2 single crystal. Results show up the rare earth influence on the XMCD structure at the transition metal K edge in these alloys.