Redetermination of AgPO3

Abstract

Single crystals of silver(I) polyphosphate(V), AgPO3, were prepared via a phosphoric acid melt method using a solution of Ag 3PO4 in H3PO4. In comparison with the previous study based on single-crystal Weissenberg photographs [Jost (1961). Acta Cryst. 14, 779-784], the results were mainly confirmed, but with much higher precision and with all displacement parameters refined anisotropically. The structure is built up from two types of distorted edge- and corner-sharing [AgO5] polyhedra, giving rise to multidirectional ribbons, and from two types of PO4 tetrahedra linked into meandering chains (PO 3)n spreading parallel to the b axis with a repeat unit of four tetrahedra. The calculated bond-valence sum value of one of the two AgI ions indicates a significant strain of the structure.