DOI: 10.17188/1717433
title: Materials Data on NaAlSiO4 by Materials Project

description: NaAlSiO4 crystallizes in the orthorhombic Pmc2_1 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 2.29–2.46 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 2.31–2.49 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 four equivalent SiO6 octahedra, edges with two equivalent AlO6 octahedra, and edges with two equivalent SiO6 octahedra. The corner-sharing octahedra tilt angles range from 49–54°. There are a spread of Al–O bond distances ranging from 1.90–2.03 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with four equivalent SiO6 octahedra, edges with two equivalent AlO6 octahedra, and edges with two equivalent SiO6 octahedra. The corner-sharing octahedra tilt angles range from 47–53°. There are a spread of Al–O bond distances ranging from 1.88–2.07 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to six O2- atoms to form SiO6 octahedra that share corners with four equivalent AlO6 octahedra, edges with two equivalent AlO6 octahedra, and edges with two equivalent SiO6 octahedra. The corner-sharing octahedra tilt angles range from 47–53°. There are a spread of Si–O bond distances ranging from 1.80–1.87 Å. In the second Si4+ site, Si4+ is bonded to six O2- atoms to form SiO6 octahedra that share corners with four equivalent AlO6 octahedra, edges with two equivalent AlO6 octahedra, and edges with two equivalent SiO6 octahedra. The corner-sharing octahedra tilt angles range from 49–54°. There are a spread of Si–O bond distances ranging from 1.82–1.85 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, two equivalent Al3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, one Al3+, and two equivalent Si4+ atoms. In the third O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, two equivalent Al3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, one Al3+, and two equivalent Si4+ atoms. In the fifth O2- site, O2- is bonded to two equivalent Na1+, two equivalent Al3+, and one Si4+ atom to form distorted ONa2Al2Si trigonal bipyramids that share corners with two equivalent ONa2Al2Si trigonal bipyramids, edges with two equivalent ONa2AlSi2 square pyramids, and edges with three ONa2Al2Si trigonal bipyramids. In the sixth O2- site, O2- is bonded to two equivalent Na1+, one Al3+, and two equivalent Si4+ atoms to form distorted ONa2AlSi2 square pyramids that share corners with two equivalent ONa2Al2Si trigonal bipyramids, edges with two equivalent ONa2AlSi2 square pyramids, and edges with four ONa2Al2Si trigonal bipyramids. In the seventh O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Na1+, one Al3+, and two equivalent Si4+ atoms. In the eighth O2- site, O2- is bonded to two equivalent Na1+, two equivalent Al3+, and one Si4+ atom to form distorted ONa2Al2Si trigonal bipyramids that share corners with two equivalent ONa2AlSi2 square pyramids, corners with six ONa2Al2Si trigonal bipyramids, edges with two equivalent ONa2AlSi2 square pyramids, and an edgeedge with one ONa2Al2Si trigonal bipyramid.