Crystal structures and magnetic properties of two octacyanometalate-based tungstate(v)–copper(ii) bimetallic assemblies

Abstract

Two novel cyanide-bridged bimetallic assemblies based on octacyanotungstate as the building block, [Cu(tn)₂]₂[W(CN)₈](OH)·H₂O (1) and {[Cu(dien)]₂[W(CN)₈](OH)·3H₂O}_∞ (2) (tn = 1,3-diaminopropane; dien = diethylenetriamine), have been prepared and their magnetic properties studied. The X-ray analysis shows that the structure of 1 consists of a trinuclear unit, Cu(tn)₂–N–C–W(CN)₆–C–N–Cu(tn)₂, which acts as a basic component that is connected through weak axial Cu⋯N–C–W interactions to form a two-dimensional sheet network. In the structure of 2, each W(CN)₈ fragment connects four Cu(dien) groups through two types of W–C–N–Cu linkages in a –(A–B)_n– pattern along the diagonal lines of the a and b axes to form an infinite 2-D layer structure. Magnetic susceptibility data demonstrate that the magnetic behavior of both 1 and 2 is characteristic of ferromagnetic interactions onto which weak antiferromagnetic interactions are superimposed.