Neutron Diffraction Study of the Pseudobinary System ErCo2–ErAl2

Abstract
Results obtained by neutron diffraction indicate that the magnetic moment of the ferromagnetic sublattice in the Laves phase structures, C15 (ErCo2, ErAl2) and C14 (ErCoAl), varies with composition while the ordering temperatures stay approximately constant. Low values of the aligned moment, however, are accompanied by high values of the disorder scattering at low temperatures. Co carries no moment from 30 mole % ErAl2 on. Results are discussed in terms of tendencies toward antiferromagnetism at certain values for the valence electron concentration.