DOI: 10.17188/1290765
title: Materials Data on Na7Ti13O26 by Materials Project

description: Na7Ti13O26 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are four inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with six TiO6 octahedra, edges with two NaO6 octahedra, and edges with six TiO6 octahedra. The corner-sharing octahedra tilt angles range from 13–19°. There are a spread of Na–O bond distances ranging from 2.41–2.45 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with six TiO6 octahedra, edges with two NaO6 octahedra, and edges with six TiO6 octahedra. The corner-sharing octahedra tilt angles range from 12–21°. There are a spread of Na–O bond distances ranging from 2.42–2.48 Å. In the third Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with six TiO6 octahedra, edges with three NaO6 octahedra, and edges with six TiO6 octahedra. The corner-sharing octahedra tilt angles range from 10–16°. There are a spread of Na–O bond distances ranging from 2.39–2.45 Å. In the fourth Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with six TiO6 octahedra, edges with two equivalent NaO6 octahedra, and edges with six TiO6 octahedra. The corner-sharing octahedra tilt angles range from 13–19°. There are a spread of Na–O bond distances ranging from 2.42–2.45 Å. There are seven inequivalent Ti+3.46+ sites. In the first Ti+3.46+ site, Ti+3.46+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four NaO6 octahedra, edges with three NaO6 octahedra, and edges with six TiO6 octahedra. The corner-sharing octahedra tilt angles range from 10–19°. There are a spread of Ti–O bond distances ranging from 1.98–2.08 Å. In the second Ti+3.46+ site, Ti+3.46+ is bonded to six O2- atoms to form TiO6 octahedra that share a cornercorner with one NaO6 octahedra, edges with four NaO6 octahedra, and edges with six TiO6 octahedra. The corner-sharing octahedral tilt angles are 13°. There are a spread of Ti–O bond distances ranging from 1.99–2.04 Å. In the third Ti+3.46+ site, Ti+3.46+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with six NaO6 octahedra, edges with two NaO6 octahedra, and edges with six TiO6 octahedra. The corner-sharing octahedra tilt angles range from 13–16°. There are a spread of Ti–O bond distances ranging from 1.98–2.07 Å. In the fourth Ti+3.46+ site, Ti+3.46+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three NaO6 octahedra, edges with three NaO6 octahedra, and edges with six TiO6 octahedra. The corner-sharing octahedra tilt angles range from 16–21°. There are a spread of Ti–O bond distances ranging from 1.98–2.06 Å. In the fifth Ti+3.46+ site, Ti+3.46+ is bonded to six O2- atoms to form TiO6 octahedra that share edges with four NaO6 octahedra and edges with six TiO6 octahedra. There are two shorter (2.00 Å) and four longer (2.01 Å) Ti–O bond lengths. In the sixth Ti+3.46+ site, Ti+3.46+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two NaO6 octahedra, edges with four NaO6 octahedra, and edges with six TiO6 octahedra. The corner-sharing octahedra tilt angles range from 14–15°. There are a spread of Ti–O bond distances ranging from 1.99–2.07 Å. In the seventh Ti+3.46+ site, Ti+3.46+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with five NaO6 octahedra, edges with three NaO6 octahedra, and edges with six TiO6 octahedra. The corner-sharing octahedra tilt angles range from 11–19°. There are a spread of Ti–O bond distances ranging from 2.02–2.06 Å. There are thirteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Na1+ and three Ti+3.46+ atoms. In the second O2- site, O2- is bonded to two Na1+ and three Ti+3.46+ atoms to form ONa2Ti3 square pyramids that share corners with five ONa2Ti3 square pyramids, corners with two equivalent ONaTi3 trigonal pyramids, edges with five ONa2Ti3 square pyramids, and an edgeedge with one ONaTi3 trigonal pyramid. In the third O2- site, O2- is bonded to two Na1+ and three Ti+3.46+ atoms to form ONa2Ti3 square pyramids that share corners with four ONa2Ti3 square pyramids, corners with three ONaTi3 trigonal pyramids, edges with six ONa2Ti3 square pyramids, and an edgeedge with one ONaTi3 trigonal pyramid. In the fourth O2- site, O2- is bonded to two Na1+ and three Ti+3.46+ atoms to form ONa2Ti3 square pyramids that share corners with seven ONa2Ti3 square pyramids, a cornercorner with one ONaTi3 trigonal pyramid, edges with five ONa2Ti3 square pyramids, and an edgeedge with one ONaTi3 trigonal pyramid. In the fifth O2- site, O2- is bonded to two Na1+ and three Ti+3.46+ atoms to form ONa2Ti3 square pyramids that share corners with five ONa2Ti3 square pyramids, a cornercorner with one ONaTi3 trigonal pyramid, and edges with four ONa2Ti3 square pyramids. In the sixth O2- site, O2- is bonded to one Na1+ and three Ti+3.46+ atoms to form distorted ONaTi3 trigonal pyramids that share corners with eight ONa2Ti3 square pyramids, edges with three ONa2Ti3 square pyramids, and an edgeedge with one ONaTi3 trigonal pyramid. In the seventh O2- site, O2- is bonded to two Na1+ and three Ti+3.46+ atoms to form ONa2Ti3 square pyramids that share corners with three ONa2Ti3 square pyramids, corners with two equivalent ONaTi3 trigonal pyramids, edges with five ONa2Ti3 square pyramids, and edges with two equivalent ONaTi3 trigonal pyramids. In the eighth O2- site, O2- is bonded in a distorted see-saw-like geometry to one Na1+ and three Ti+3.46+ atoms. In the ninth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Na1+ and three Ti+3.46+ atoms. In the tenth O2- site, O2- is bonded to one Na1+ and three Ti+3.46+ atoms to form distorted ONaTi3 trigonal pyramids that share corners with six ONa2Ti3 square pyramids, a cornercorner with one ONaTi3 trigonal pyramid, and edges with five ONa2Ti3 square pyramids. In the eleventh O2- site, O2- is bonded to two equivalent Na1+ and three Ti+3.46+ atoms to form ONa2Ti3 square pyramids that share corners with five ONa2Ti3 square pyramids, a cornercorner with one ONaTi3 trigonal pyramid, edges with seven ONa2Ti3 square pyramids, and an edgeedge with one ONaTi3 trigonal pyramid. In the twelfth O2- site, O2- is bonded to two Na1+ and three Ti+3.46+ atoms to form ONa2Ti3 square pyramids that share corners with four ONa2Ti3 square pyramids, corners with three ONaTi3 trigonal pyramids, edges with six ONa2Ti3 square pyramids, and an edgeedge with one ONaTi3 trigonal pyramid. In the thirteenth O2- site, O2- is bonded to two equivalent Na1+ and three Ti+3.46+ atoms to form ONa2Ti3 square pyramids that share corners with eight ONa2Ti3 square pyramids, a cornercorner with one ONaTi3 trigonal pyramid, edges with six ONa2Ti3 square pyramids, and an edgeedge with one ONaTi3 trigonal pyramid.