Magnetic and structural transitions in NdS, DyS and ErS

Magnetic susceptibility measurements on single crystals of metallic NdS, DyS and ErS indicate a simultaneous antiferromagnetic and structural transition at 11, 34 and 7.3 K, respectively. Below this transition the anisotropy of χ corresponds to a tetragonal distortion for all three compounds. The small distortion in the case of ErS is anamolous in two respects: it can be switched by a large applied magnetic field and a trigonal distortion would have been expected from simple theory. © 1974.