Synthesis and crystal structure of NaCuIn(PO₄)₂

Area of Science:

• Inorganic Chemistry
• Crystallography
• Materials Science

Background:

• Crystal structure determination is crucial for understanding material properties.
• Phosphate compounds exhibit diverse structural motifs and potential applications.

Purpose of the Study:

• To synthesize and characterize single crystals of sodium copper(II) indium bis-[phosphate(V)], NaCuIn(PO4)2.
• To elucidate the crystal structure and bonding of the title compound.

Main Methods:

• Single crystal growth from melt under atmospheric conditions.
• X-ray diffraction analysis to determine crystal structure and space group.
• Analysis of coordination polyhedra and structural connectivity.

Main Results:

• NaCuIn(PO4)2 crystallizes in the P21/n space group, isotypic with KCuFe(PO4)2.
• The structure features [Cu2O8] dimers linked to PO4 tetrahedra, forming sheets.
• These sheets are sandwiched between layers of PO4 tetrahedra and InO6 octahedra, creating a 3D framework with channels.

Conclusions:

• The 3D framework of NaCuIn(PO4)2 is built from alternating layers and interconnected polyhedra.
• Channels within the framework host sodium cations coordinated by four oxygen atoms.
• The study provides detailed structural insights into a novel copper-indium phosphate material.