Synthesis and magnetic properties of Cu oxides with low-dimensional structure

We report the synthesis and magnetic properties of Cu oxides with low-dimensional structure. For CuSb2−x TixO6 compounds with tri-rutile type structure, magnetic susceptibility χ showed that a characteristic temperature, J/kB, where a broad maximum of χ appears due to the short-range antiferromagnetic order, decreases with increase of x. Thus, it is considered that a hole carrier doped by Ti substitution results in the decrease of J/kB. Furthermore, it was found that the antiferromagnetic long-range order at the transition temperature (TN), around 8.5 K for x = 0.0, still remains in the substituted compounds for x = 0.3, which indicates the one-dimensional interaction along the diagonal direction is dominant. CuNb2−x TixO6 compounds have zig-zag chain structure in the edge-sharing CuO6 octahedra. Temperature dependences of χ were found to be well analyzed by the alternating 1DHAF model. Hole doping into this material is realaized by substituting Ti4+ ions for Sb5+ ions.