Syntheses, structures and magnetic properties of two neutral coordination polymers of cobalt(II) containing a tailored aromatic diamine and pseudohalides as bridging units: Control of dimensionality by varying pseudohalide

Two neutral coordination polymers of the types 2D [Co(bnzd)(dca)2]n (1) and 3D [Co(bnzd)(N3)2]n (2) (bnzd = benzidine; dca = dicyanamide) have been synthesized and characterized. X-ray structural analyses reveal that each cobalt(II) center in 1 and 2 is hexacoordinated with octahedral geometry. Compound 1 has a 2D sheet structure with a (4,4) topology bridged through bidentate bnzd and double μ1,5 dca units. An extended 3D network structure in 2 is seen formed by μ1,3-azide and bidentate bnzd bridges. Variable-temperature magnetic susceptibility measurements of 1 and 2 show antiferromagnetic coupling among the cobalt(II) centers mediated through pseudohalide bridges.