Synthesis, crystal structure, and magnetic properties of a copper(II) octacyanotungstate(V)-based magnet containing two types of organic ligands

Cu-3[W(CN)(8)](2)(pyrimidine)(2)(3-cyanopyridine)(2)center dot 4H(2)O, a cyanide-bridged copper(II) octacyanotungstate(V) with two types of organic ligands (pyrimidine and 3-cyanopyridine), is prepared. In this compound. the coordination geometry of W is an 8-coordinated bicapped trigonal prism where five CN groups of [W(CN)(8)] are bridged to five Cu ions, and the remaining three CN groups are free. The coordination geometries of the three types of Cu ions (Cu1, Cu2, and Cu3) are 6-coordinated pseudo-octahedron. The cyano-bridged-Cu2-W-Cu3-layer is linked by a Cut pillar unit, and a cavity along the a axis, which is occupied by 3-cyanopyridine molecules and zeolitic water molecules, exists. The present compound shows ferrimagnetism with a Currie temperature of 7 K, a saturation magnetization of 2.9/mu(B), and a coercive field of 7 Oe at 2 K. (C) 2008 Elsevier Ltd. All rights reserved.