Synthesis, Crystal structures and Magnetic properties of two new Hetero-bimetallic assemblies

Abstract

Two new cyanide-bridged 3d–4f hetero-dinuclear complexes, namely Ln(DMF)4(H2O)3(μ-CN)Co(CN)5 · H2O (Ln = Nd (1) and Gd (2), DMF = N,N-dimethylformamide), were synthesized by the facile reaction of LnCl3 · 6H2O and K3Co(CN)6. Characterization includes microanalysis, IR spectrometric identifications, X-ray crystallographic analysis and magnetic properties. Both 1 and 2 crystallize in the centrosymmetric monoclinic space group P 2 /n (No. 14) with Z = 4. The lanthanide(III) ions are eight-coordinate in a square-antiprism arrangement, while cobalt(III) ions are six-coordinate in an octahedral environment in each complex. A cyanide bridge links an Ln(III) ion to a Co(III) ion. Molecules in the crystal cell of each compound are held together by van der Waals forces and a network of hydrogen bonding. Magnetic analysis shows that antiferromagnetic interactions are observed below 7 K for both 1 and 2, which are attributed to intermolecular interactions between the Ln(III) ions in the network through hydrogen bonds. This series of compounds may be of importance in photo-induced magnetism because of the cyanide bridge between 3d and 4f metals.