Non-collinear magnetic structure of the Sr2ErRuO6 double perovskite

The crystal and magnetic structure of Sr 2 ErRuO 6 has been studied by means of neutron powder diffraction as well as magnetization and susceptibility measurements. Neutron diffraction profile measured at 50 K shows that the Ru 5+ and Er 3+ are ordered in the B-sites of the perovskite-type structure, while the Sr atoms occupy the A-site. This compound crystallizes with a monoclinic unit cell, space group P 2 1 / n and lattice parameters are approximately √2 a p × √2 a p × 2 a p . Magnetic susceptibility measurements reveal the existence of antiferromagnetic interactions in which Ru 5+ and Er 3+ sublattices are involved. The field dependence of the magnetization indicates the presence of a weak ferromagnetic component at the transition temperature, arising from the spin canting of the antiferromagnetically ordered Ru 5+ and Er 3+ moments. Thermal evolution of the neutron diffraction patterns indicate that the Neel temperature is 36 K and the magnetic reflections can be indexed on the basis of a propagation vector k = [0, 0, 0]. The spin arrangement is described by the A x A z magnetic modes where the Ru 5+ and Er 3+ moments are mainly aligned along the c -axis of the structure, forming an angle of ∼6° with the c -axis in the case of the Er 3+ sublattice and ∼15° for the Ru 5+ moment.