Crystal structure of bis-(ammonium) bis-[penta-aqua-(di-methyl-formamide)-zinc(II)] deca-vanadate tetra-hydrate.

The crystalline product (NH 4 ) 2 [Zn(C 3 H 7 NO)(H 2 O) 5 ] 2 [V 10 O 28 ]·4H 2 O was success-fully isolated from an H 2 O/DMF solvent combination by evaporation at ambient temperature. The salt crystallizes in the P 2 1 / n space group. Imidazole, initially used in the synthesis but not present in the product, and DMF solvent appear to affect the synthesis and crystallization as structural-directing agents. In the title compound, the complex cation [Zn(H 2 O) 5 (DMF)] 2+ acts as a counter-ion without being directly coordinated to the deca-vanadate anion. An extensive framework of hydrogen bonds integrates the whole architecture as evidenced by X-ray crystallography. The polyoxometalate [V 10 O 28 ] 6- lies on a center of symmetry while the complex cation [Zn(H 2 O) 5 (DMF)] 2+ links three adjacent anions through a set of 2 + 2 + 3 hydrogen bonds.