Materials Data on Na2ZnFe2(PO4)3 by Materials Project

Abstract

Na2Fe2Zn(PO4)3 is Esseneite-derived structured and crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.43–2.86 Å. In the second Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.35–2.94 Å. Fe+2.50+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six PO4 tetrahedra, an edgeedge with one FeO6 octahedra, and an edgeedge with one ZnO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.97–2.16 Å. Zn2+ is bonded to six O2- atoms to form distorted ZnO6 octahedra that share corners with six PO4 tetrahedra and edges with two equivalent FeO6 octahedra. There are a spread of Zn–O bond distances ranging from 2.13–2.24 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent ZnO6 octahedra and corners with four equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 52–61°. There is two shorter (1.54 Å) and two longer (1.57 Å) P–O bond length. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent ZnO6 octahedra and corners with four equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 37–58°. There are a spread of P–O bond distances ranging from 1.55–1.57 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Na1+, one Fe+2.50+, and one P5+ atom. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na1+, one Zn2+, and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, one Fe+2.50+, one Zn2+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Fe+2.50+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Na1+, one Fe+2.50+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, one Fe+2.50+, one Zn2+, and one P5+ atom.