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DOE OSTI · 1694790

Materials Data on Na4Sn2Ge5O17 by Materials Project

Abstract

Na4Sn2Ge5O17 crystallizes in the monoclinic P2 space group. The structure is three-dimensional. there are four inequivalent Na sites. In the first Na site, Na is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Na–O bond distances ranging from 2.28–2.55 Å. In the second Na site, Na is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.39–2.93 Å. In the third Na site, Na is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Na–O bond distances ranging from 2.32–2.51 Å. In the fourth Na site, Na is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Na–O bond distances ranging from 2.40–2.81 Å. There are two inequivalent Sn sites. In the first Sn site, Sn is bonded to six O atoms to form SnO6 octahedra that share corners with six GeO4 tetrahedra. There are a spread of Sn–O bond distances ranging from 2.07–2.11 Å. In the second Sn site, Sn is bonded to six O atoms to form SnO6 octahedra that share corners with six GeO4 tetrahedra. There are a spread of Sn–O bond distances ranging from 2.08–2.11 Å. There are six inequivalent Ge sites. In the first Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with three SnO6 octahedra and a cornercorner with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 40–55°. There are a spread of Ge–O bond distances ranging from 1.76–1.82 Å. In the second Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with two equivalent SnO6 octahedra and corners with two GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 50–54°. There are a spread of Ge–O bond distances ranging from 1.76–1.80 Å. In the third Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with three SnO6 octahedra and a cornercorner with one GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 40–55°. There are a spread of Ge–O bond distances ranging from 1.76–1.81 Å. In the fourth Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with two equivalent SnO6 octahedra and corners with two GeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–53°. There are a spread of Ge–O bond distances ranging from 1.75–1.81 Å. In the fifth Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with two equivalent SnO6 octahedra and corners with two equivalent GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 45°. There is two shorter (1.75 Å) and two longer (1.79 Å) Ge–O bond length. In the sixth Ge site, Ge is bonded to four O atoms to form GeO4 tetrahedra that share corners with two equivalent SnO6 octahedra and corners with two equivalent GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 40°. There is two shorter (1.74 Å) and two longer (1.80 Å) Ge–O bond length. There are eighteen inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to one Na and two Ge atoms. In the second O site, O is bonded in a trigonal planar geometry to one Na and two Ge atoms. In the third O site, O is bonded in a distorted trigonal planar geometry to one Na, one Sn, and one Ge atom. In the fourth O site, O is bonded in a 3-coordinate geometry to two Na, one Sn, and one Ge atom. In the fifth O site, O is bonded in a distorted trigonal pyramidal geometry to two Na, one Sn, and one Ge atom. In the sixth O site, O is bonded in a distorted trigonal planar geometry to one Na, one Sn, and one Ge atom. In the seventh O site, O is bonded in a distorted trigonal planar geometry to one Na, one Sn, and one Ge atom. In the eighth O site, O is bonded in a distorted trigonal planar geometry to one Na, one Sn, and one Ge atom. In the ninth O site, O is bonded in a distorted T-shaped geometry to one Na, one Sn, and one Ge atom. In the tenth O site, O is bonded in a distorted trigonal planar geometry to one Na, one Sn, and one Ge atom. In the eleventh O site, O is bonded in a distorted trigonal planar geometry to one Na, one Sn, and one Ge atom. In the twelfth O site, O is bonded in a 3-coordinate geometry to two Na, one Sn, and one Ge atom. In the thirteenth O site, O is bonded in a distorted T-shaped geometry to one Na, one Sn, and one Ge atom. In the fourteenth O site, O is bonded in a distorted trigonal planar geometry to one Na and two Ge atoms. In the fifteenth O site, O is bonded in a trigonal planar geometry to one Na and two Ge atoms. In the sixteenth O site, O is bonded in a 4-coordinate geometry to two Na, one Sn, and one Ge atom. In the seventeenth O site, O is bonded in an L-shaped geometry to two equivalent Na atoms. In the eighteenth O site, O is bonded in an L-shaped geometry to two equivalent Na atoms.

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2020-04-30. Materials Data on Na4Sn2Ge5O17 by Materials Project. https://doi.org/10.17188/1694790

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36 MATERIALS SCIENCE↗