Sr(5)(VOF(5))(3)F(H(2)O)(3) refined from a non-merohedrally twinned crystal

The title compound, penta-strontium tris-[penta-fluorido-oxido-vanadate(IV)] fluoride trihydrate, was obtained under hydro-thermal conditions. Its crystal structure has been refined from intensity data of a non-merohedrally twinned crystal. Two domains in almost equal proportions are related by a -180° rotation along the reciprocal [101]* vector. The structure may be considered as a derivative of the fluorite structure type, adopted here by SrF(2). In the title compound, fluorite-like large rods are recognized, built up from a group of 16 Sr atoms of which 6 are substituted by V atoms, leading to [Sr(10)V(6)](∞) units. These rods extend infinitely along the b axis and are inter-connected by the three water mol-ecules. Each of the water mol-ecules is shared by two different Sr atoms belonging to two different rods. The rods are also inter-connected by an 'independent' F atom in a distorted triangular [FSr(3)] coordination and by hydrogen-bonding inter-actions via donor water mol-ecules. The acceptors are either F atoms or the O atoms of the vanadyl ion, VO(2+), that is part of the [VOF(5)] isolated octa-hedron.