Structural and physical properties of SrMn1-xRuxO3 perovskites

We combine the results of magnetic and transport measurements with neutron-diffraction data to construct the structural and magnetic phase diagram of the entire family of SrMn1-xRuxO3 (0 <= x <= 1) perovskites. We have found antiferromagnetic (AF) ordering of the C type for lightly Ru-substituted materials (0.06 <= x <= 0.5) in a similar manner to RySr1-yMnO3 (R=La,Pr) due to the generation of Mn3+ in both families of manganite perovskites by either B-site substitution of Ru5+ for Mn4+ or A-site substitution of R3+ for Sr2+. This similarity is driven by the same ratio of d(4)/d(3) ions in both classes of materials for equivalent substitution level. In both cases, a tetragonal lattice distortion is observed, which for some compositions (0.06 <= x <= 0.2) is coupled to a C-type AF transition and results in a first-order magnetic and resistive transition. Heavily substituted SrMn1-xRuxO3 materials are ferromagnetic due to dominating exchange interactions between the Ru4+ ions. Intermediate substitution (0.6 <= x <= 0.7) leads to a spin-glass behavior instead of a quantum critical point reported previously in single crystals due to enhanced disorder.