Circumventing the perovskite pattern: Linear ruthenate(V) polyoxoanions in Bi2NaRuO6

Abstract

Phase pure, coarse crystalline Bi2NaRuO6 was synthesized in a hydrothermal approach. It displays a new crystal structure (Prima (62), a = 12.1408(1) angstrom, b = 7.49282(6) angstrom, c = 12.1163(1) angstrom, z = 8), which is characterized by a quasi-1D poly-oxoanion composed of (RuO6) octahedra sharing oxygen atoms in trans position. The magnetic response at high temperatures is described by a Curie-Weiss law reflecting strong antiferromagnetic interactions. The obtained effective magnetic moment complies with the d(3) configuration for Ru5+. Below 208 K a weakly ferromagnetic state evolves while no phase transition could be observed in a heat capacity measurement. The compound displays activated electrical conduction. The overall composition and the ionic radii ratios of the constituents encourage to apply elevated hydrostatic pressure in order to realize the title compound in a double perovskite type arrangement, instead of the chain-like structure encountered at ambient conditions.