Unusual Two‐Dimensional Nickel( II ) Complexes Based on [Ni(dien)] 2+ and [M(CN) 4 ] 2− Building Blocks (M = Ni, Pd and Pt) − Synthesis, Structural Diversity and Magnetic Properties

Three novel polymeric compounds [Ni(dien)Ni(CN) 4 ] n (H 2 O) n ( 1 ), [Ni(dien)Pd(CN) 4 ] n ( 2 ), and [Ni(dien)Pt(CN) 4 ] n ( 3 ) were synthesised by reaction of [{Ni(dien)(H 2 O)} 2 (μ‐ox)](PF 6 ) 2 with [M(CN) 4 ] 2− (M = Ni, Pd, Pt) in aqueous solution. The structure of these compounds contains two [Ni(dien)] 2+ cationic units bridged by two [M(CN) 4 ] 2− anions in a cis fashion, generating a square‐shaped [Ni 2 −M 2 ] metal core. The different linking modes between the cores afford a 2D bilayer with encapsulated water in compound 1 and corrugated layers in compounds 2 and 3 . These coordination modes are compared to the different bridging modes of tetracyanometalate‐containing compounds retrieved from the CSD database. The three compounds present a very weak antiferromagnetic coupling between the octahedrally coordinated Ni II ions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)