A new one-dimensional system starting from a trinuclear copper(II) complex and selenocyanate as bridging ligand. Comparison with the thiocyanate analogue

Abstract

A new copper(II) bridging-selenocyanate complex has been synthesized starting from the known trinuclear copper(II) complex, [{Cu(tmen)} ₂ {µ-Cu(pba)}][ClO ₄ ] ₂ [tmen = N,N,N′, N′-tetramethylethane-1,2-diamine and H ₄ pba = N,N′- propane-1,3-diylbis(oxamic acid)]. The reaction of an aqueous solution of this complex with KSeCN gave good crystals of the new one-dimensional compound in which two selenocyanate ligands are linked to each terminal copper(II) ion. Both these ligands are weakly Se-coupled to the central copper(II) atom of another trinuclear entity giving a pseudo one(two)-dimensional structure. The magnetic behaviour was recorded between 300 and 4 K, showing strong intramolecular antiferromagnetic coupling (J = -356 cm ^-1 , g _C = 2.20 and g _T = 2.21; C = central, T = terminal Cu atom) and very weak intermolecular ferromagnetic coupling.