Crystal structure of SrCo4(OH)(PO4)3, a new hydroxyphosphate

Single crystals of strontium tetracobalt tris(orthophosphate) hydroxide, SrCo4(OH)(PO4)3, were grown serendipitously under hydrothermal conditions at 473 K. The crystal structure consists of undulating chains of edge-sharing [CoO6] octahedra that are linked into (010) layers by common vertices between chains. Adjacent layers are linked along [010] into a framework structure by tetrahedral [CoO4] units and by PO4 tetrahedra. The framework delimits channels extending along [100] in which the eleven-coordinate strontium cations are situated. Bifurcated O—H...O hydrogen bonds of weak strengths consolidate the crystal packing. The title compound was also characterized by infrared spectroscopy.