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DOE OSTI · 1727946

Materials Data on BaTi6O11 by Materials Project

Abstract

BaTi6O11 crystallizes in the orthorhombic Cmc2_1 space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form distorted BaO12 cuboctahedra that share corners with ten TiO6 octahedra, edges with two equivalent TiO6 octahedra, a faceface with one BaO12 cuboctahedra, and faces with six TiO6 octahedra. The corner-sharing octahedra tilt angles range from 41–50°. There are a spread of Ba–O bond distances ranging from 2.78–3.22 Å. In the second Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form distorted BaO12 cuboctahedra that share corners with twelve TiO6 octahedra, edges with three TiO6 octahedra, a faceface with one BaO12 cuboctahedra, and faces with four TiO6 octahedra. The corner-sharing octahedra tilt angles range from 14–53°. There are a spread of Ba–O bond distances ranging from 2.70–3.21 Å. There are seven inequivalent Ti+3.33+ sites. In the first Ti+3.33+ site, Ti+3.33+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three BaO12 cuboctahedra, a cornercorner with one TiO6 octahedra, an edgeedge with one BaO12 cuboctahedra, and edges with six TiO6 octahedra. The corner-sharing octahedral tilt angles are 59°. There are a spread of Ti–O bond distances ranging from 1.87–2.15 Å. In the second Ti+3.33+ site, Ti+3.33+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three BaO12 cuboctahedra, corners with four TiO6 octahedra, an edgeedge with one BaO12 cuboctahedra, and edges with three TiO6 octahedra. The corner-sharing octahedra tilt angles range from 40–59°. There are a spread of Ti–O bond distances ranging from 1.89–2.17 Å. In the third Ti+3.33+ site, Ti+3.33+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with two BaO12 cuboctahedra, corners with two TiO6 octahedra, edges with four TiO6 octahedra, and faces with two BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 4–12°. There are a spread of Ti–O bond distances ranging from 1.99–2.10 Å. In the fourth Ti+3.33+ site, Ti+3.33+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three BaO12 cuboctahedra, corners with four TiO6 octahedra, edges with four TiO6 octahedra, and a faceface with one BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 4–47°. There are a spread of Ti–O bond distances ranging from 1.97–2.10 Å. In the fifth Ti+3.33+ site, Ti+3.33+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ti–O bond distances ranging from 1.81–2.38 Å. In the sixth Ti+3.33+ site, Ti+3.33+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with three TiO6 octahedra, edges with six TiO6 octahedra, and faces with two BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 4–5°. There are a spread of Ti–O bond distances ranging from 1.99–2.15 Å. In the seventh Ti+3.33+ site, Ti+3.33+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with five TiO6 octahedra, an edgeedge with one BaO12 cuboctahedra, edges with four TiO6 octahedra, and faces with two BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 4–51°. There are a spread of Ti–O bond distances ranging from 1.97–2.07 Å. There are thirteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to one Ba2+ and four Ti+3.33+ atoms. In the second O2- site, O2- is bonded in a distorted T-shaped geometry to one Ba2+ and three Ti+3.33+ atoms. In the third O2- site, O2- is bonded in a distorted T-shaped geometry to one Ba2+ and three Ti+3.33+ atoms. In the fourth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ba2+ and three Ti+3.33+ atoms. In the fifth O2- site, O2- is bonded to one Ba2+ and four Ti+3.33+ atoms to form distorted OBaTi4 trigonal bipyramids that share an edgeedge with one OBaTi4 trigonal bipyramid and an edgeedge with one OTi4 trigonal pyramid. In the sixth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ba2+ and four Ti+3.33+ atoms. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+ and three Ti+3.33+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Ba2+ and two equivalent Ti+3.33+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two Ba2+ and two Ti+3.33+ atoms. In the tenth O2- site, O2- is bonded in a distorted T-shaped geometry to two Ba2+ and three Ti+3.33+ atoms. In the eleventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ba2+ and four Ti+3.33+ atoms. In the twelfth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Ba2+ and three Ti+3.33+ atoms. In the thirteenth O2- site, O2- is bonded to four Ti+3.33+ atoms to form distorted edge-sharing OTi4 trigonal pyramids.

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2020-05-02. Materials Data on BaTi6O11 by Materials Project. https://doi.org/10.17188/1727946

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36 MATERIALS SCIENCE↗