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Updated: Feb 28, 2026
Molten-Salt Synthesis of Complex Metal Oxide Nanoparticles
Published on: October 27, 2018
Crystal structure of a silver-, cobalt- and iron-based phosphate with an alluaudite-like structure:
Adam Bouraima1,2, Thomas Makani2, Abderrazzak Assani1
1Laboratoire de Chimie du Solide Appliquée, Faculty of Sciences, Mohammed V University in Rabat, Avenue Ibn Battouta, BP 1014, Rabat, Morocco.
Abstract:
The new silver-, cobalt- and iron-based phosphate, silver cobalt iron tris(ortho-phosphate), Ag1.655Co1.64Fe1.36(PO4)3, was synthesized by solid-state reactions. Its structure is isotypic to that of Na2Co2Fe(PO4)3, and belongs to the alluaudite family, with a partial cationic disorder, the AgI atoms being located on an inversion centre and twofold rotation axis sites (Wyckoff positions 4a and 4e), with partial occupancies of 0.885 (2) and 0.7688 (19), respectively. One of the two P atoms in the asymmetric unit completely fills one 4e site while the Co and Fe atoms fill another 4e site, with partial occupancies of 0.86 (5) and 0.14 (5), respectively. The remaining Co2+ and Fe3+ cations are distributed on a general position, 8f, in a 0.39 (4):0.61 (4) ratio. All O atoms and the other P atoms are in general positions. The structure is built up from zigzag chains of edge-sharing [MO6] (M = Fe/Co) octa-hedra stacked parallel to [101]. These chains are linked together through PO4 tetra-hedra, forming polyhedral sheets perpendicular to [010]. The resulting framework displays two types of channels running along [001], in which the AgI atoms (coordination number eight) are located.
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