MAGNETIC CIRCULAR-DICHROISM OF GD-CO AND GD-NI ALLOYS IN THE GD 3D, 4D AND THE (CO, NI) 2P, 3P CORE EXCITATION REGIONS - ANTIFERROMAGNETIC COUPLING BETWEEN GD AND (CO, NI) MOMENTS

Magnetic circular dichroism(MCD) spectra of Gd-Co and Gd-Ni alloys wer e measured in core excitation regions using evaporated film and are-me lted bulk samples. Antiferromagnetic coupling between spins of rare-ea rth and transition metals was demonstrated in Gd-Co but it was not the case in bulk Gd-Ni, which gives rise to a possible spin-glass-like st ate at the liquid nitrogen temperature with the help of hidden ferroma gnetic interaction.