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DOE OSTI · 1193593

Materials Data on BaV6O11 by Materials Project

Abstract

BaV6O11 crystallizes in the hexagonal P6_3mc space group. The structure is three-dimensional. Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with six equivalent BaO12 cuboctahedra, edges with six equivalent VO6 octahedra, edges with three equivalent VO5 trigonal bipyramids, and faces with six VO6 octahedra. There are six shorter (2.86 Å) and six longer (2.97 Å) Ba–O bond lengths. There are four inequivalent V+3.33+ sites. In the first V+3.33+ site, V+3.33+ is bonded to five O2- atoms to form VO5 trigonal bipyramids that share corners with twelve VO6 octahedra and edges with three equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 43–56°. There are a spread of V–O bond distances ranging from 1.90–2.26 Å. In the second V+3.33+ site, V+3.33+ is bonded to six O2- atoms to form VO6 octahedra that share corners with six equivalent VO6 octahedra, corners with three equivalent VO5 trigonal bipyramids, faces with three equivalent BaO12 cuboctahedra, and a faceface with one VO6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are three shorter (2.02 Å) and three longer (2.08 Å) V–O bond lengths. In the third V+3.33+ site, V+3.33+ is bonded to six O2- atoms to form VO6 octahedra that share corners with six equivalent VO6 octahedra, corners with three equivalent VO5 trigonal bipyramids, faces with three equivalent BaO12 cuboctahedra, and a faceface with one VO6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are three shorter (2.02 Å) and three longer (2.08 Å) V–O bond lengths. In the fourth V+3.33+ site, V+3.33+ is bonded to six O2- atoms to form VO6 octahedra that share corners with four VO6 octahedra, corners with two equivalent VO5 trigonal bipyramids, edges with two equivalent BaO12 cuboctahedra, and edges with four equivalent VO6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of V–O bond distances ranging from 1.97–2.06 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to four V+3.33+ atoms. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to four V+3.33+ atoms. In the third O2- site, O2- is bonded in a 5-coordinate geometry to two equivalent Ba2+ and three V+3.33+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+ and three V+3.33+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+ and three V+3.33+ atoms.

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2020-07-24. Materials Data on BaV6O11 by Materials Project. https://doi.org/10.17188/1193593

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36 MATERIALS SCIENCE↗