Magnetic Properties of Some Rare‐Earth Gold Compounds

A magnetic susceptibility study of the b.c. tetragonal MoSi2‐type intermetallic compounds RAu2, where R is one of the heavy rare earths, has been made at temperatures from 2.5 to 300°K in applied fields up to 26 kOe. The temperature dependence of the inverse susceptibility at high temperatures for these compounds followed the Curie‐Weiss law giving effective moments close to those of the trivalent rare‐earth ions. At low temperatures antiferromagnetic behaviour was observed in all of these compounds. In addition, a first order magnetic transition was observed below their Neel temperatures for TbAu2 and DyAu2. These observations are in agreement with the neutron diffraction results of Atoji. The results are interpreted by using the RKKY interaction along with an anisotropic field term.