Crystal structure, magnetism and spectroscopy of bis(tetraphenylphosphonium)tetrakis(dicyanamido)cobaltate(II) with bridging and pendant dicyanamide ligands

The synthesis, structure and magnetic properties of the cobalt(II) complex, (Ph₄P)₂Co(NCNCN)₄] (1) is reported. The compound crystallises in the monoclinic system, space group C2/c, with cell constants: β=105.65(2)°, Z=4 and The structure of 1 consists of octahedral CoN₆ chromophores with uni- and bidentate N(CN)₂ ligands. Cobalt atoms are doubly bridged by bidentate NCNCN groups forming infinite ribbons along the crystallographic b-axis. As first representative of an anionic dicyanamide complex 1 behaves as a weak ferromagnet at low temperatures.