Abstract

An ambiguity arises in the study by powder neutron diffraction of compounds where the magnetic atoms lie on a uniaxial or cubic Bravais lattice, when the magnetic lines are indexed {kl} or {l}. Many multiaxial configurations, all having the same isotropic coupling energy, are compatible with a given set of lines. For a simple cubic lattice it is shown that every multiaxial configuration is indistinguishable, using powder intensities, from a particular uniaxial one, and that both have the same dipolar energy.