DOI: 10.17188/1719587
title: Materials Data on Na2Ti12O25 by Materials Project

description: Na2Ti12O25 crystallizes in the monoclinic P2/m space group. The structure is three-dimensional. Na1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Na–O bond distances ranging from 2.50–2.97 Å. There are six inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 28–30°. There are a spread of Ti–O bond distances ranging from 1.83–2.23 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 0–28°. There are a spread of Ti–O bond distances ranging from 1.84–2.18 Å. In the third Ti4+ site, Ti4+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing TiO6 octahedra. The corner-sharing octahedra tilt angles range from 30–33°. There are a spread of Ti–O bond distances ranging from 1.78–2.29 Å. In the fourth Ti4+ site, Ti4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.79–2.33 Å. In the fifth Ti4+ site, Ti4+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.77–2.29 Å. In the sixth Ti4+ site, Ti4+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 34°. There are a spread of Ti–O bond distances ranging from 1.81–2.27 Å. There are thirteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to two Ti4+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to two equivalent Na1+ and two Ti4+ atoms. In the third O2- site, O2- is bonded to four Ti4+ atoms to form distorted OTi4 trigonal pyramids that share a cornercorner with one ONa2Ti2 tetrahedra, corners with three OTi4 trigonal pyramids, and edges with two equivalent OTi4 trigonal pyramids. In the fourth O2- site, O2- is bonded in a linear geometry to two equivalent Ti4+ atoms. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Na1+ and two Ti4+ atoms. In the sixth O2- site, O2- is bonded in a distorted T-shaped geometry to three Ti4+ atoms. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to four Ti4+ atoms. In the eighth O2- site, O2- is bonded in a linear geometry to two Ti4+ atoms. In the ninth O2- site, O2- is bonded to two equivalent Na1+ and two Ti4+ atoms to form distorted ONa2Ti2 tetrahedra that share corners with two equivalent ONa2Ti2 tetrahedra, a cornercorner with one OTi4 trigonal pyramid, and an edgeedge with one OTi4 trigonal pyramid. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to three Ti4+ atoms. In the eleventh O2- site, O2- is bonded to four Ti4+ atoms to form a mixture of distorted edge and corner-sharing OTi4 trigonal pyramids. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to three Ti4+ atoms. In the thirteenth O2- site, O2- is bonded to four Ti4+ atoms to form distorted OTi4 trigonal pyramids that share corners with three OTi4 trigonal pyramids and an edgeedge with one ONa2Ti2 tetrahedra.