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DOE OSTI · 1203995

Materials Data on Ca11(ReO6)4 by Materials Project

Abstract

Ca11Re4O24 crystallizes in the tetragonal I4_1 space group. The structure is three-dimensional. there are seven inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with two equivalent ReO6 octahedra and edges with two equivalent ReO6 octahedra. The corner-sharing octahedral tilt angles are 73°. There are a spread of Ca–O bond distances ranging from 2.37–2.43 Å. In the second Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with two equivalent ReO6 octahedra and edges with two equivalent ReO6 octahedra. The corner-sharing octahedral tilt angles are 69°. There are a spread of Ca–O bond distances ranging from 2.37–2.44 Å. In the third Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.72 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.24–2.53 Å. In the fifth Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.25–2.55 Å. In the sixth Ca2+ site, Ca2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ca–O bond distances ranging from 2.43–3.03 Å. In the seventh Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.39–2.61 Å. There are two inequivalent Re+6.50+ sites. In the first Re+6.50+ site, Re+6.50+ is bonded to six O2- atoms to form ReO6 octahedra that share edges with two CaO6 octahedra. There are a spread of Re–O bond distances ranging from 1.90–1.94 Å. In the second Re+6.50+ site, Re+6.50+ is bonded to six O2- atoms to form ReO6 octahedra that share corners with two CaO6 octahedra. The corner-sharing octahedra tilt angles range from 69–73°. There are a spread of Re–O bond distances ranging from 1.86–2.05 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Re+6.50+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Re+6.50+ atom. In the third O2- site, O2- is bonded to three Ca2+ and one Re+6.50+ atom to form distorted corner-sharing OCa3Re trigonal pyramids. In the fourth O2- site, O2- is bonded to three Ca2+ and one Re+6.50+ atom to form a mixture of distorted corner and edge-sharing OCa3Re tetrahedra. In the fifth O2- site, O2- is bonded to three Ca2+ and one Re+6.50+ atom to form a mixture of distorted corner and edge-sharing OCa3Re trigonal pyramids. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Re+6.50+ atom. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to three Ca2+ and one Re+6.50+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Re+6.50+ atom. In the ninth O2- site, O2- is bonded in a distorted see-saw-like geometry to three Ca2+ and one Re+6.50+ atom. In the tenth O2- site, O2- is bonded in a 5-coordinate geometry to four Ca2+ and one Re+6.50+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to four Ca2+ and one Re+6.50+ atom. In the twelfth O2- site, O2- is bonded in a 5-coordinate geometry to four Ca2+ and one Re+6.50+ atom.

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2020-04-30. Materials Data on Ca11(ReO6)4 by Materials Project. https://doi.org/10.17188/1203995

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