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DOE OSTI · 1302353

Materials Data on Ca5Ge3O11 by Materials Project

Abstract

Ca5Ge3O11 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are five inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.93 Å. In the second Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with two equivalent CaO6 octahedra and corners with six GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 66–73°. There are a spread of Ca–O bond distances ranging from 2.31–2.58 Å. In the third Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.32–2.95 Å. In the fourth Ca2+ site, Ca2+ is bonded to six O2- atoms to form distorted CaO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with six GeO4 tetrahedra, and an edgeedge with one CaO6 octahedra. The corner-sharing octahedra tilt angles range from 66–73°. There are a spread of Ca–O bond distances ranging from 2.37–2.43 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 2.27–2.56 Å. There are three inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with six CaO6 octahedra. The corner-sharing octahedra tilt angles range from 49–75°. There are a spread of Ge–O bond distances ranging from 1.76–1.80 Å. In the second Ge4+ site, Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with two equivalent CaO6 octahedra and a cornercorner with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–57°. There are a spread of Ge–O bond distances ranging from 1.75–1.82 Å. In the third Ge4+ site, Ge4+ is bonded to four O2- atoms to form distorted GeO4 tetrahedra that share corners with four CaO6 octahedra and a cornercorner with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–69°. There are a spread of Ge–O bond distances ranging from 1.74–1.90 Å. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Ca2+ and one Ge4+ atom. In the second O2- site, O2- is bonded to three Ca2+ and one Ge4+ atom to form distorted corner-sharing OCa3Ge trigonal pyramids. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Ca2+ and two Ge4+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to three Ca2+ and one Ge4+ atom. In the fifth O2- site, O2- is bonded to three Ca2+ and one Ge4+ atom to form a mixture of distorted edge and corner-sharing OCa3Ge tetrahedra. In the sixth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Ca2+ and one Ge4+ atom. In the seventh O2- site, O2- is bonded to three Ca2+ and one Ge4+ atom to form a mixture of distorted edge and corner-sharing OCa3Ge tetrahedra. In the eighth O2- site, O2- is bonded to three Ca2+ and one Ge4+ atom to form a mixture of distorted edge and corner-sharing OCa3Ge trigonal pyramids. In the ninth O2- site, O2- is bonded to three Ca2+ and one Ge4+ atom to form a mixture of distorted edge and corner-sharing OCa3Ge tetrahedra. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to three Ca2+ and one Ge4+ atom. In the eleventh O2- site, O2- is bonded in a 5-coordinate geometry to four Ca2+ and one Ge4+ atom.

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2020-07-20. Materials Data on Ca5Ge3O11 by Materials Project. https://doi.org/10.17188/1302353

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36 MATERIALS SCIENCE↗