Crystal Structure and Magnetic Properties of an Octacyanometalate-Based Three-Dimensional Tungstate(V)−Manganese(II) Bimetallic Assembly

A single crystal of the title compound [MnII 6(H2O)9{WV(CN)8}4·13H2O] n was synthesized in a hot aqueous solution containing octacyanotungstate, Na3[W(CN)8]·3H2O, and Mn(ClO4)2·6H2O. The compound crystallized in the monoclinic system, space group P21/c with cell constants a = 15.438(2) Å, b= 14.691(2) Å, c = 33.046(2) Å, β = 94.832(9)°, and Z = 4. The crystal consists of a WV−CN−MnII linked three-dimensional network [{MnII(H2O)}3{MnII(H2O)2 }3{WV(CN)8}4] n and H2O molecules as crystal solvates. There are two kinds of W sites: one is close to a dodecahedron geometry with six bridging and two terminal CN ligands; the other is close to a bicapped trigonal prism with seven bridging and one terminal CN ligands. The field-cooled magnetization measurement showed that the compound exhibits a spontaneous magnetization below T c = 54 K. Further magnetization measurements on the field dependence reveal it to be a ferrimagnet where all of the Mn II ions are antiparallel to all the WV ions.