High-temperature magnetic properties of AnFe2 (An = Np,Pu, Am) Laves phases

Magnetization measurements have been performed on NpFe₂, PuFe₂, and AmFe₂ (cubic C15-type Laves phase) between 300 and 1100 K. The Curie temperatures were found to be 492 ± 2, 564 ± 2, and 613 ± 3 K, respectively. A correlation was found between the Curie temperature and the magnetic moment per iron atom determined in previous neutron-diffraction experiments. Critical exponents determined for NpFe₂ and PuFe₂ were found to be close to previously reported values for the chemically ordered metallic system Pd₃Fe. The overall magnetic behavior of the compounds studied implies the presence of local magnetic moments, in contrast to the itinerant magnetic behavior of UFe₂ noted in the previous paper.