Crystal structure, Mössbauer spectroscopy and magnetic properties of a new potassium iron oxyphosphate K11Fe15(PO4)18O related to the Langbeinite-like compounds

Besma Lajmi (1) , Mourad Hidouri (1) , Alain Wattiaux (2) , Léopold Fournès (2) , Jacques Darriet (2) , Mongi Ben Amara (1)

1 Laboratoire de Chimie Structurale des Matériaux, Département de Chimie
2 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

new potassium iron phosphate K11Fe15(PO4)18O has been synthesized by the flux method and characterized by single-crystal X-ray diffraction. The compound crystallizes in the cubic system with the space group P213 and the cell parameter a=9.917(2) Å. The unit cell contains one formula unit K7.33Fe10(PO4)12O0.66. The structure is closely related to that of the Langbeinite-like compounds, the main difference being the existence of a four-coordinated iron atom in the structure of the oxyphosphate. K11Fe15(PO4)18O adopts a complex three-dimensional network involving corner- and edge-linkage between iron polyhedra, and corner-sharing between phosphorus tetrahedra and iron polyhedra...

Mots clés: Transition metal compounds; Crystal structure; Mössbauer spectroscopy; Magnetic measurements

Domaines: Matériaux

Besma Lajmi, Mourad Hidouri, Alain Wattiaux, Léopold Fournès, Jacques Darriet, et al.. Crystal structure, Mössbauer spectroscopy and magnetic properties of a new potassium iron oxyphosphate K11Fe15(PO4)18O related to the Langbeinite-like compounds. Journal of Alloys and Compounds, 2003, 361 (1-2), pp.77-83. ⟨10.1016/S0925-8388(03)00412-2⟩. ⟨hal-00175001⟩