Crystal structure of a new tripotassium hexa-nickel iron hexa-phosphate.

A new potassium-nickel iron phosphate, KNiFe(PO), has been synthesized by solid-state reaction and structurally characterized by single-crystal X-ray diffraction and qualitative energy dispersive X-ray spectroscopy (EDS) analysis. The structure is built up by [FeO], [PO], and [NiO] coordination polyhedra, which are linked to each other by edge and corner sharing to form zigzag layers parallel to the plane. These layers are inter-connected by [PO] tetra-hedra and [NiO] octa-hedra common corners, leading to a three-dimensional framework delimiting large channels running along the [100] direction in which the K cations are localized.