Crystal structure of silver strontium copper orthophosphate, AgSr4Cu4.5(PO4)6

• Published in: Acta crystallographica. Section E, Crystallographic communications Vol. 76; no. Pt 2; pp. 186 - 191
• Main Authors: Khmiyas, Jamal, Benhsina, Elhassan, Ouaatta, Said, Assani, Abderrazzak, Saadi, Mohamed, El Ammari, Lahcen
• Format: Journal Article
• Language: English
• Published: International Union of Crystallography 01.02.2020
• Subjects: agsr4cu4.5(po4)6; crystal structure; hydrothermal synthesis; layered structure; Research Communications; transition metal phosphate
• ISSN: 2056-9890; 2056-9890
• DOI: 10.1107/S2056989020000109

Crystals of the new compound, AgSr4Cu4.5(PO4)6, were grown successfully by the hydro-thermal process. The asymmetric unit of the crystal structure of the title compound contains 40 independent atoms (4 Sr, 4.5 Cu, 1 Ag, 6 P and 24 O), which are all in general positions except for one Cu atom, which is located on an inversion centre. The Cu atoms are arranged in CuO n (n = 4 or 5) polyhedra, linked through common oxygen corners to build a rigid three-dimensional motif. The connection of these copper units is assured by PO4 tetra-hedra. This arrangement allows the construction of layers extending parallel to the (100) plane and hosts suitable cavities in which Ag+ and Sr2+ cations are located. The crystal-structure cohesion is ensured by ionic bonds between the silver and strontium cations and the oxygen anions belonging to two adjacent sheets. Charge-distribution analysis and bond-valence-sum calculations were used to validate the structural model.