One-Dimensional Iron(III) and Two-Dimensional Iron(III)Nickel(II) Cyanide-Bridged Ferromagnetic Arrays from Hexacyanoferrate(III) and [Ni(cyclam)]2± Building Blocks: Synthesis, Crystal Structure and Magnetic Properties

The X-ray structures and magnetic properties of a iron(III) linear chain and a honeycomb-like layered iron(III)-nickel(III) cyanide-bridged compound are reported. The former contains alternating iron sites and unexpected ferromagnetic behaviour, justified on the basis of the axial distortion from regular octahedral geometry of one of the iron ions. The latter is metamagnetic with ferromagnetic intralayers and antiferromagnetic interlayers interactions with a Neel temperature, T-N = 77 K. The field-induced transition from an antiferro- to a ferromagnetic state takes place at Hc = 5000 G. The antiferromagnetic ordered phase exhibits spin-canting and long range ferromagnetic ordering at 3 K with a characteristic hysteresis loop.