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DOE OSTI · 1720702

Materials Data on Cs2Na6Al6Ge7O30 by Materials Project

Abstract

Cs2Na6Al6Ge7O30 crystallizes in the trigonal P3 space group. The structure is three-dimensional. there are two inequivalent Cs sites. In the first Cs site, Cs is bonded in a 6-coordinate geometry to six equivalent O atoms. There are three shorter (3.19 Å) and three longer (3.64 Å) Cs–O bond lengths. In the second Cs site, Cs is bonded in a 6-coordinate geometry to six equivalent O atoms. There are three shorter (3.19 Å) and three longer (3.65 Å) Cs–O bond lengths. There are two inequivalent Na sites. In the first Na site, Na is bonded to five O atoms to form distorted NaO5 square pyramids that share corners with three AlO4 tetrahedra, corners with three GeO4 tetrahedra, corners with two equivalent NaO5 trigonal bipyramids, and an edgeedge with one GeO6 octahedra. There are a spread of Na–O bond distances ranging from 2.34–2.58 Å. In the second Na site, Na is bonded to five O atoms to form distorted NaO5 trigonal bipyramids that share corners with two equivalent GeO6 octahedra, corners with two equivalent NaO5 square pyramids, corners with three AlO4 tetrahedra, and corners with three GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 21–62°. There are a spread of Na–O bond distances ranging from 2.38–2.49 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with two equivalent NaO5 square pyramids, corners with four GeO4 tetrahedra, and a cornercorner with one NaO5 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.76–1.78 Å. In the second Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share a cornercorner with one NaO5 square pyramid, corners with four GeO4 tetrahedra, and corners with two equivalent NaO5 trigonal bipyramids. There are a spread of Al–O bond distances ranging from 1.76–1.78 Å. There are three inequivalent Ge sites. In the first Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with two equivalent NaO5 square pyramids, corners with four AlO4 tetrahedra, and a cornercorner with one NaO5 trigonal bipyramid. There is two shorter (1.76 Å) and two longer (1.77 Å) Ge–O bond length. In the second Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share a cornercorner with one NaO5 square pyramid, corners with four AlO4 tetrahedra, and corners with two equivalent NaO5 trigonal bipyramids. There is one shorter (1.76 Å) and three longer (1.77 Å) Ge–O bond length. In the third Ge site, Ge is bonded to six O atoms to form GeO6 octahedra that share corners with six equivalent NaO5 trigonal bipyramids and edges with three equivalent NaO5 square pyramids. There is three shorter (1.86 Å) and three longer (1.88 Å) Ge–O bond length. There are ten inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to one Na, one Al, and one Ge atom. In the second O site, O is bonded in a distorted trigonal planar geometry to one Na, one Al, and one Ge atom. In the third O site, O is bonded in a distorted T-shaped geometry to two Na and one Ge atom. In the fourth O site, O is bonded in a distorted trigonal non-coplanar geometry to two Na and one Ge atom. In the fifth O site, O is bonded in a 2-coordinate geometry to two equivalent Cs, one Al, and one Ge atom. In the sixth O site, O is bonded in a 2-coordinate geometry to two equivalent Cs, one Al, and one Ge atom. In the seventh O site, O is bonded in a distorted trigonal planar geometry to one Na, one Al, and one Ge atom. In the eighth O site, O is bonded in a distorted trigonal non-coplanar geometry to one Na, one Al, and one Ge atom. In the ninth O site, O is bonded in a distorted trigonal planar geometry to one Na, one Al, and one Ge atom. In the tenth O site, O is bonded in a distorted trigonal planar geometry to one Na, one Al, and one Ge atom.

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2020-04-30. Materials Data on Cs2Na6Al6Ge7O30 by Materials Project. https://doi.org/10.17188/1720702

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