BaZnRu5O11: Novel compound with frustrated magnetic lattice based on a distorted kagome network

Single crystals of the novel compound BaZnRu5O11 were grown from a barium chloride flux. The composition was determined from refinements of single crystal X-ray diffraction data and microprobe analysis. BaZnRu5O11 crystallizes in a supercell of the R-type ferrite structure with doubled a and b unit cell parameters (space group P63/m, Z = 8, a = 11.7411(2) Å, c = 13.6842(4) Å). The reason for the superstructure is the formation of Ru–Ru pairs with short distances within the idealized kagome net extending in (001). No indication of Zn/Ru mixed occupied sites was observed. BaZnRu5O11 does not show any sign of magnetic ordering down to 1.8 K. A large negative Curie–Weiss temperature ΘW⊥ = −290 K (ΘW|| = −230 K) suggests strong Ru3+ (S = ½) antiferromagnetic interactions frustrated on the kagome network of this compound. It is suggested that distortion of the well-ordered kagome sublattice gives rise to unusual behaviour of magnetic and electrical transport properties at low temperatures: BaZnRu5O11 single crystals exhibit a susceptibility χ∼1−T and electrical resistivity ρ ∼ T1.6 below about 10 K which may indicate a non-Fermi liquid.

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► In this study crystals of a novel oxoruthenate were grown.
► The crystal structure reveals kagome nets as one building unit, distorted via Ru–Ru chemical bonds.
► Strong antiferromagnetic interactions are frustrated on the kagome net.
► Below 10 K a non-Fermi liquid behavior was indicated.