Ni(2)Sr(PO(4))(2)·2H(2)O

Abstract

The title compound, dinickel(II) strontium bis-[ortho-phosphate(V)] dihydrate, was obtained under hydro-thermal conditions. The crystal structure consists of linear chains (∞) (1)[NiO(2/2)(OH(2))(2/2)O(2/1)] of edge-sharing NiO(6) octa-hedra ( symmetry) running parallel to [010]. Adjacent chains are linked to each other through PO(4) tetra-hedra (m symmetry) and arranged in such a way to build layers parallel to (001). The three-dimensional framework is accomplished by stacking of adjacent layers that are held together by SrO(8) polyhedra (2/m symmetry). Two types of O-H⋯O hydrogen bonds involving the water mol-ecule are present, viz. one very strong hydrogen bond perpendicular to the layers and weak trifurcated hydrogen bonds parallel to the layers.

Fig. 1.

Partial plot of Ni2Sr(PO4)2,2H2O crystal structure. Displacement ellipsoids are drawn at the 50% probability level. Symmetry codes: (i) x - 1/2, -y + 3/2, z; (ii) -x + 3/2, y - 1/2, -z; (iii) -x + 3/2, -y + 3/2, -z; (iv) x - 1/2, y - 1/2, z; (v) -x + 1, -y + 1, -z; (vi) x - 1/2, y + 1/2, z; (vii) -x + 3/2, -y + 1/2, -z; (viii) -x + 3/2, -y + 3/2, -z + 1; (ix) -x + 2, y, -z + 1; (x) x + 1/2, y + 1/2, z + 1; (xi) x, -y + 1, z; (xii) x + 1/2, y - 1/2, z; (xiii) x + 1/2, y + 1/2, z; (xiv) -x + 3/2, y - 1/2, -z + 1; (xv) -x + 2, -y + 1, -z + 1.

Fig. 2.

A three-dimensional polyhedral view of the crystal structure of the Ni2Sr(PO4)2.2H2O, showing the stacking of layers along the c axis and the hydrogen bonding scheme (dashed lines).