Materials Data on Na3Fe(PO4)2 by Materials Project

Abstract

Na3Fe(PO4)2 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 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.35–2.87 Å. In the second Na1+ site, Na1+ is bonded in a 2-coordinate geometry to nine O2- atoms. There are a spread of Na–O bond distances ranging from 2.34–3.06 Å. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six equivalent PO4 tetrahedra. There are a spread of Fe–O bond distances ranging from 2.01–2.11 Å. P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 28–51°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to three equivalent Na1+, one Fe3+, and one P5+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+, one Fe3+, and one P5+ atom. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to three Na1+, one Fe3+, and one P5+ atom.