DOI: 10.17188/1686597
title: Materials Data on Na9Fe2P4HO18 by Materials Project

description: Na9Fe2P4HO18 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are nine inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.29–2.43 Å. In the second Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.24–2.52 Å. In the third 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 2.37–2.80 Å. In the fourth 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 2.36–2.60 Å. In the fifth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with two PO4 tetrahedra, and edges with two PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 57–59°. There are a spread of Na–O bond distances ranging from 2.38–2.58 Å. In the sixth Na1+ site, Na1+ is bonded in a distorted square co-planar geometry to four O2- atoms. There are a spread of Na–O bond distances ranging from 2.42–2.48 Å. In the seventh 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 2.36–2.73 Å. In the eighth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.32–2.42 Å. In the ninth 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 2.43–2.79 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent NaO6 octahedra, corners with two equivalent FeO6 octahedra, and corners with four PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–59°. There are a spread of Fe–O bond distances ranging from 1.90–2.10 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra and corners with four PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–50°. There are a spread of Fe–O bond distances ranging from 1.90–2.10 Å. There are four inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one NaO6 octahedra and corners with two FeO6 octahedra. The corner-sharing octahedra tilt angles range from 43–64°. There is one shorter (1.55 Å) and three longer (1.56 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 FeO6 octahedra and an edgeedge with one NaO6 octahedra. The corner-sharing octahedral tilt angles are 46°. There are a spread of P–O bond distances ranging from 1.54–1.58 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two FeO6 octahedra and an edgeedge with one NaO6 octahedra. The corner-sharing octahedral tilt angles are 50°. There is one shorter (1.54 Å) and three longer (1.56 Å) P–O bond length. In the fourth P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share a cornercorner with one NaO6 octahedra and corners with two FeO6 octahedra. The corner-sharing octahedra tilt angles range from 48–62°. There are a spread of P–O bond distances ranging from 1.55–1.57 Å. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded to five Na1+ and one P5+ atom to form distorted ONa5P octahedra that share corners with two equivalent ONa5P octahedra and a cornercorner with one ONa2Fe2 tetrahedra. The corner-sharing octahedral tilt angles are 7°. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Na1+ and one P5+ atom. In the third O2- site, O2- is bonded in a 6-coordinate geometry to five Na1+ and one P5+ atom. In the fourth O2- site, O2- is bonded to two Na1+ and two Fe3+ atoms to form distorted corner-sharing ONa2Fe2 tetrahedra. The corner-sharing octahedral tilt angles are 28°. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+, one Fe3+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Na1+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe3+, and one P5+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the ninth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+, one Fe3+, and one P5+ atom. In the tenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Na1+, one Fe3+, and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe3+, and one P5+ atom. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+, one Fe3+, and one P5+ atom. In the thirteenth O2- site, O2- is bonded in a 1-coordinate geometry to four Na1+ and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Fe3+, and one P5+ atom. In the fifteenth O2- site, O2- is bonded in a distorted single-bond geometry to one Na1+, two Fe3+, and one H1+ atom. In the sixteenth O2- site, O2- is bonded in a 1-coordinate geometry to five Na1+ and one P5+ atom. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one P5+ atom. In the eighteenth O2- site, O2- is bonded in a 1-coordinate geometry to four Na1+ and one P5+ atom.