A new eight-coordinate complex of manganese(II): synthesis, crystal structure, spectroscopy and magnetic properties of [Mn(Hoxam)2(H2O)4] (H2oxam=oxamic acid)

The crystal structure of an eight-coordinate manganese(II) compound containing oxamato and water molecules as ligands [Mn(Hoxam)2(H2O)4], were H2oxam=oxamic acid, has been determined by X-ray diffraction on single-crystals. The coordinated oxygen atoms are located at the vertices (corners) of a distorted bicapped trigonal antiprism. Hydrogen bonding is responsible for an extended 3D-network. The magnetic susceptibility data of the compound have been investigated. χMT follows the Curie law, at very low temperatures χMT decreases smoothly due to weak intermolecular interactions and/or due to a small zero field splitting of the sextuplet spin state of the Mn(II).