DOI: 10.17188/1292572
title: Materials Data on Na8Nb5O14 by Materials Project

description: Na8Nb5O14 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are nine inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share a cornercorner with one NbO6 octahedra, corners with two NaO6 octahedra, an edgeedge with one NbO6 octahedra, and edges with six NaO6 octahedra. The corner-sharing octahedra tilt angles range from 15–18°. There are a spread of Na–O bond distances ranging from 2.32–2.56 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 2.29–2.48 Å. In the third 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 2.32–2.78 Å. In the fourth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two equivalent NaO6 octahedra, edges with two NbO6 octahedra, and edges with six NaO6 octahedra. The corner-sharing octahedra tilt angles range from 17–18°. There are a spread of Na–O bond distances ranging from 2.31–2.65 Å. In the fifth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share a cornercorner with one NbO6 octahedra, corners with two NaO6 octahedra, an edgeedge with one NbO6 octahedra, and edges with six NaO6 octahedra. The corner-sharing octahedra tilt angles range from 15–23°. There are a spread of Na–O bond distances ranging from 2.37–2.65 Å. In the sixth Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with two NaO6 octahedra, corners with three NbO6 octahedra, edges with two NbO6 octahedra, and edges with seven NaO6 octahedra. The corner-sharing octahedra tilt angles range from 5–16°. There are a spread of Na–O bond distances ranging from 2.36–2.58 Å. In the seventh Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share a cornercorner with one NaO6 octahedra, corners with two equivalent NbO6 octahedra, edges with three NbO6 octahedra, and edges with six NaO6 octahedra. The corner-sharing octahedra tilt angles range from 8–24°. There are a spread of Na–O bond distances ranging from 2.40–2.68 Å. In the eighth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two NbO6 octahedra, corners with four NaO6 octahedra, edges with four NbO6 octahedra, and edges with five NaO6 octahedra. The corner-sharing octahedra tilt angles range from 11–24°. There are a spread of Na–O bond distances ranging from 2.27–2.54 Å. In the ninth Na1+ site, Na1+ is bonded to six O2- atoms to form NaO6 octahedra that share corners with two equivalent NaO6 octahedra, corners with two equivalent NbO6 octahedra, edges with four NbO6 octahedra, and edges with eight NaO6 octahedra. The corner-sharing octahedra tilt angles range from 6–16°. There are a spread of Na–O bond distances ranging from 2.33–2.47 Å. There are five inequivalent Nb4+ sites. In the first Nb4+ site, Nb4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Nb–O bond distances ranging from 1.84–2.35 Å. In the second Nb4+ site, Nb4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Nb–O bond distances ranging from 1.86–2.34 Å. In the third Nb4+ site, Nb4+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share a cornercorner with one NbO6 octahedra, corners with four NaO6 octahedra, edges with three NbO6 octahedra, and edges with six NaO6 octahedra. The corner-sharing octahedra tilt angles range from 8–23°. There are a spread of Nb–O bond distances ranging from 1.88–2.25 Å. In the fourth Nb4+ site, Nb4+ is bonded to six O2- atoms to form NbO6 octahedra that share a cornercorner with one NbO6 octahedra, corners with three NaO6 octahedra, edges with three NbO6 octahedra, and edges with five NaO6 octahedra. The corner-sharing octahedra tilt angles range from 5–13°. There are a spread of Nb–O bond distances ranging from 2.02–2.29 Å. In the fifth Nb4+ site, Nb4+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with three NaO6 octahedra, edges with four NaO6 octahedra, and edges with five NbO6 octahedra. The corner-sharing octahedra tilt angles range from 6–13°. There are a spread of Nb–O bond distances ranging from 2.19–2.28 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted see-saw-like geometry to three Na1+ and one Nb4+ atom. In the second O2- site, O2- is bonded in a 6-coordinate geometry to four Na1+ and two Nb4+ atoms. In the third O2- site, O2- is bonded to four Na1+ and two Nb4+ atoms to form distorted ONa4Nb2 octahedra that share corners with three ONa3Nb2 square pyramids, a cornercorner with one ONa3Nb2 trigonal bipyramid, edges with five ONb6 octahedra, an edgeedge with one ONa4Nb square pyramid, and an edgeedge with one ONa3Nb2 trigonal bipyramid. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to four Na1+ and two Nb4+ atoms. In the fifth O2- site, O2- is bonded to four Na1+ and one Nb4+ atom to form distorted ONa4Nb square pyramids that share corners with four ONb6 octahedra, a cornercorner with one ONa3Nb2 square pyramid, corners with three ONa3Nb2 trigonal bipyramids, edges with two ONa5Nb octahedra, and an edgeedge with one ONa4Nb square pyramid. The corner-sharing octahedra tilt angles range from 7–10°. In the sixth O2- site, O2- is bonded to three Na1+ and two Nb4+ atoms to form distorted ONa3Nb2 trigonal bipyramids that share corners with three ONa5Nb octahedra, corners with four ONa3Nb2 square pyramids, a cornercorner with one ONa3Nb2 trigonal bipyramid, edges with two ONb6 octahedra, an edgeedge with one ONa3Nb2 square pyramid, and an edgeedge with one ONa3Nb2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 3–36°. In the seventh O2- site, O2- is bonded to three Na1+ and two Nb4+ atoms to form distorted ONa3Nb2 trigonal bipyramids that share corners with three ONb6 octahedra, corners with three ONa3Nb2 square pyramids, edges with four ONb6 octahedra, and an edgeedge with one ONa3Nb2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 7–12°. In the eighth O2- site, O2- is bonded to six Nb4+ atoms to form ONb6 octahedra that share corners with two ONa5Nb octahedra, a cornercorner with one ONa4Nb square pyramid, a cornercorner with one ONa3Nb2 trigonal bipyramid, edges with four ONb6 octahedra, edges with three ONa3Nb2 square pyramids, and edges with two ONa3Nb2 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 9–14°. In the ninth O2- site, O2- is bonded to five Na1+ and one Nb4+ atom to form distorted ONa5Nb octahedra that share corners with two ONb6 octahedra, a cornercorner with one ONa2Nb3 square pyramid, a cornercorner with one ONa3Nb2 trigonal bipyramid, edges with five ONa5Nb octahedra, edges with two ONa3Nb2 square pyramids, and an edgeedge with one ONa3Nb2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 0–9°. In the tenth O2- site, O2- is bonded to three Na1+ and two Nb4+ atoms to form distorted ONa3Nb2 square pyramids that share a cornercorner with one ONa4Nb2 octahedra, corners with three ONa3Nb2 square pyramids, corners with two ONa3Nb2 trigonal bipyramids, edges with four ONb6 octahedra, and an edgeedge with one ONa3Nb2 trigonal bipyramid. The corner-sharing octahedral tilt angles are 12°. In the eleventh O2- site, O2- is bonded to five Na1+ and one Nb4+ atom to form distorted ONa5Nb octahedra that share corners with two ONb6 octahedra, corners with two ONa2Nb3 square pyramids, a cornercorner with one ONa3Nb2 trigonal bipyramid, edges with five ONa5Nb octahedra, edges with three ONa3Nb2 square pyramids, and an edgeedge with one ONa3Nb2 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 0–14°. In the twelfth O2- site, O2- is bonded to two equivalent Na1+ and three Nb4+ atoms to form ONa2Nb3 square pyramids that share corners with four ONa5Nb octahedra, a cornercorner with one ONa3Nb2 square pyramid, corners with two ONa3Nb2 trigonal bipyramids, edges with five ONb6 octahedra, and an edgeedge with one ONa2Nb3 square pyramid. The corner-sharing octahedra tilt angles range from 9–84°. In the thirteenth O2- site, O2- is bonded to three Na1+ and three Nb4+ atoms to form ONa3Nb3 octahedra that share a cornercorner with one ONa3Nb3 octahedra, corners with two ONa2Nb3 square pyramids, corners with two ONa3Nb2 trigonal bipyramids, edges with seven ONb6 octahedra, edges with two ONa3Nb2 square pyramids, and an edgeedge with one ONa3Nb2 trigonal bipyramid. The corner-sharing octahedral tilt angles are 0°. In the fourteenth O2- site, O2- is bonded in a 6-coordinate geometry to four Na1+ and two Nb4+ atoms.