Heterobimetallic assemblies of Ni(II) complexes with a tetradentate amine ligand and diamagnetic cyanidometallates

Abstract

Syntheses and crystal structures of nickel(II) complexes containing teta (teta=N,N′-bis(2-aminoethyl)ethane-1,2-diamine) as a tetradentate blocking ligand and cyanidometallic bridging complexes are described. The complexes [Ni(teta)(cis-μ2-Ni(CN)4)] (1) and [{Ni(teta)}3(μ6-Co(CN)6)] (ClO4)3 (2) exhibit a 1D-polymeric structure whereas the heterometallic trinuclear complex [Ni(teta)(μ1-Ag(CN)2)2] (3) forms a unique network. The weak antiferromagnetic exchange was found in polymeric species 1 and 2 by analyzing the magnetic data with several models in which either only susceptibility was treated or simultaneous fitting of temperature and magnetic field dependences of the magnetization was applied using the finite-size closed ring approach. Moreover, an effect of the zero-field splitting phenomenon (ZFS) was considered for 2 by advanced modeling of magnetic properties for varying axial ZFS parameter/isotropic exchange (D/J) ratios.