Ferromagnetism of SmCd

Measurements have been made of the magnetic properties and the resistivities of polycrystalline specimens of SmCd and LaCd. SmCd is found to be a ferromagnetic with a Curie point of 194K and a large magnetocrystalline anisotropy which is responsible for the highly anomalous form of the magnetisation-temperature curve below the Curie temperature. No sign is found of the transition to diamagnetism at 110K which had been reported by other workers, and it is concluded that the samarium is in a reipositive ionic state up to a temperature of at least 700K. The susceptibility obeys a Curie-Weiss law above the Curie point, in agreement with a theory which has recently been proposed, and some evidence is found for a non-colinear ferromagnetic spin structure. LaCd is a Pauli paramagnet, and has a broad superconducting transition in the region of 30K. (author)