A novel style of 2D Hofmann-type coordination polymer incorporated trigonal prismatic coordination geometry with bidentate co-ligands.

A novel 2D Hofmann-type framework was prepared with a bidentate co-ligand, 5,5'-dimethyl-2,2'-bipyridyl (dmbpy), which forces the curvature of the layer. X-ray diffraction analysis demonstrated that the coordination polymers, Mn II (dmbpy)[M V N(CN) 4 ] (M V = Mn (1) and Cr (2)), formed a considerably corrugated 2D cyanide-bridged network with a quasi C 4v symmetric building unit, [Cr V N(CN) 4 ] 2- , and trigonal prismatic coordination geometry around Mn II . Compound 2 demonstrated a metamagnetic-like ordering at 14.4 K, caused by the intra- and inter-layer antiferromagnetic interactions between Cr V ( S = 1/2) and Mn II ( S = 5/2), and a weak ferromagnetic behaviour at 2 K reflecting the single-ion anisotropy of Cr V and structural anisotropy.