Crystal structure of SrCo₄(OH)(PO₄)₃, a new hy-droxy-phosphate.

Area of Science:

• Inorganic Chemistry
• Crystallography
• Materials Science

Background:

• Strontium cobalt phosphates are of interest for their diverse structural and magnetic properties.
• Hydrothermal synthesis offers a route to crystalline materials under moderate conditions.

Purpose of the Study:

• To report the serendipitous synthesis and structural characterization of a novel strontium cobalt phosphate hydroxide compound.
• To elucidate the crystal structure and bonding of SrCo4(OH)(PO4)3.

Main Methods:

• Single crystal growth under hydrothermal conditions at 473 K.
• X-ray diffraction for crystal structure determination.
• Infrared spectroscopy for material characterization.

Main Results:

• Single crystals of strontium tetra-cobalt tris-(orthophosphate) hydroxide, SrCo4(OH)(PO4)3, were successfully grown.
• The crystal structure features undulating chains of edge-sharing [CoO6] octahedra forming layers, linked by [CoO4] and PO4 tetrahedra into a framework.
• Channels within the framework accommodate eleven-coordinate strontium cations, with weak hydrogen bonds stabilizing the packing.

Conclusions:

• The hydrothermal method is effective for synthesizing novel inorganic compounds.
• The determined crystal structure provides insights into the coordination chemistry of cobalt and strontium in this phosphate system.
• The compound SrCo4(OH)(PO4)3 represents a new addition to the family of cobalt-containing phosphate materials.