The crystal and molecular structure of ammonium vanadyl (+)-tartrate monohydrate

Abstract

The crystal structure of ammonium vanadyl (+)-tartrate has been determined by three-dimensional X-ray diffraction. The tetragonal crystals contain isolated ammonium ions and water molecules and dimeric vanadyl tartrate units [VO(tart)]₂^4–. In the vanadyl tartrate dimer each tartrate residue forms two chelate rings, each involving a deprotonated hydroxyl oxygen atom and a carboxyl oxygen atom, to two vanadium atoms. The co-ordination of the vanadium atom is a distorted trigonal bipyramid with the vanadyl oxygen atom in the equatorial plane of the bipyramid. The dimeric complex, and each tartrate residue in it, lie on a crystallographic two-fold axis. The vanadyl tartrate dimers form a three-dimensional hydrogen-bonded network with the ammonium ions and water molecules.