DOI: 10.17188/1287953
title: Materials Data on Na4AlP2HO9 by Materials Project

description: Na4Al(PO4)2(OH) crystallizes in the orthorhombic Pbcm space group. The structure is three-dimensional. there are seven 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 2.27–2.40 Å. In the second 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 2.31–2.56 Å. In the third Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two equivalent AlO6 octahedra, corners with two equivalent PO4 tetrahedra, edges with two equivalent NaO6 octahedra, and edges with two equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 68°. There are a spread of Na–O bond distances ranging from 2.37–2.58 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 2.49–2.75 Å. In the fifth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two equivalent AlO6 octahedra, corners with two equivalent PO4 tetrahedra, edges with two equivalent NaO6 octahedra, and edges with two equivalent PO4 tetrahedra. The corner-sharing octahedral tilt angles are 65°. There are a spread of Na–O bond distances ranging from 2.37–2.61 Å. In the sixth Na1+ site, Na1+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are two shorter (2.42 Å) and two longer (2.60 Å) Na–O bond lengths. In the seventh Na1+ site, Na1+ is bonded in a distorted pentagonal planar geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.24–2.40 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with two equivalent NaO6 octahedra, corners with two equivalent AlO6 octahedra, and corners with four PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–68°. There is four shorter (1.91 Å) and two longer (1.96 Å) Al–O bond length. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with two equivalent NaO6 octahedra, corners with two equivalent AlO6 octahedra, and corners with four PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 46–65°. There are a spread of Al–O bond distances ranging from 1.91–1.95 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 corners with two equivalent NaO6 octahedra and corners with two equivalent AlO6 octahedra. The corner-sharing octahedra tilt angles range from 46–64°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent NaO6 octahedra and corners with two equivalent AlO6 octahedra. The corner-sharing octahedra tilt angles range from 47–63°. There are a spread of P–O bond distances ranging from 1.54–1.57 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with two equivalent AlO6 octahedra and edges with two equivalent NaO6 octahedra. The corner-sharing octahedral tilt angles are 42°. There is two shorter (1.55 Å) and two 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 corners with two equivalent AlO6 octahedra and edges with two equivalent NaO6 octahedra. The corner-sharing octahedral tilt angles are 46°. There are a spread of P–O bond distances ranging from 1.53–1.57 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.97 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two equivalent Al3+, and one H1+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Na1+, two equivalent Al3+, and one H1+ atom. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three Na1+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to four Na1+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Al3+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to four Na1+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Al3+, and one P5+ atom. In the eighth O2- site, O2- is bonded to five Na1+ and one P5+ atom to form distorted corner-sharing ONa5P octahedra. The corner-sharing octahedral tilt angles are 5°. In the ninth O2- site, O2- is bonded to four Na1+ and one P5+ atom to form distorted ONa4P square pyramids that share corners with two equivalent ONa5P octahedra, an edgeedge with one ONa5P octahedra, and edges with two equivalent ONa4P square pyramids. The corner-sharing octahedral tilt angles are 15°. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one P5+ atom. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to one Na1+, one Al3+, and one P5+ atom. In the twelfth O2- site, O2- is bonded to five Na1+ and one P5+ atom to form distorted ONa5P octahedra that share corners with two equivalent ONa4P square pyramids, edges with two equivalent ONa5P octahedra, and an edgeedge with one ONa4P square pyramid. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Na1+, one Al3+, and one P5+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Na1+ and one P5+ atom.