Materials Data on Na2ZnFe(PO4)2 by Materials Project
Na2FeZn(PO4)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Na1+ is bonded in a 6-coordinate geometry to ten O2- atoms. There are a spread of Na–O bond distances ranging from 2.35–3.02 Å. Fe2+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six equivalent PO4 tetrahedra and edges with two equivalent ZnO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.01–2.39 Å. Zn2+ is bonded to six O2- atoms to form ZnO6 octahedra that share corners with six equivalent PO4 tetrahedra and edges with two equivalent FeO6 octahedra. There are a spread of Zn–O bond distances ranging from 1.99–2.40 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent FeO6 octahedra and corners with three equivalent ZnO6 octahedra. The corner-sharing octahedra tilt angles range from 41–52°. There are a spread of P–O bond distances ranging from 1.55–1.57 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, one Fe2+, one Zn2+, and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to three equivalent Na1+, one Fe2+, and one P5+ atom. In the third O2- site, O2- is bonded in a 3-coordinate geometry to three equivalent Na1+, one Zn2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Na1+, one Fe2+, one Zn2+, and one P5+ atom.