Two tantalum fluorides templated with tren: [H4tren](TaF7)2·H2O and [H4tren](TaF7)2

Using tris(2-aminoethyl)amine [(C2H4NH2)3N] (tren) as a template, two new tantalum fluorides are obtained by slow evaporation of solutions: [H4tren](TaF7)2·H2O (I) and [H4tren](TaF7)2 (II). The structure determinations are performed by single crystal X-ray technique. Structures of I and II are built up from isolated TaF7 distorted monocapped trigonal prisms or pentagonal bipyramids; charge balance is achieved by tetraprotonated [H4tren]4+ cations which possess a “scorpion” configuration. In I and II, TaF7 polyhedra, connected by hydrogen bonds with water molecules in I, lie in corrugated layers; hydrogen bond networks ensure the cohesion between these layers and [H4tren]4+cations.