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DOE OSTI · 1741609

Materials Data on Na4Si5Sn2O17 by Materials Project

Abstract

Na4Sn2Si5O17 crystallizes in the monoclinic C2 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 2.38–2.61 Å. In the second 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 2.37–2.60 Å. In the third Na site, Na is bonded to five O atoms to form distorted NaO5 trigonal bipyramids that share corners with four SiO4 tetrahedra, an edgeedge with one SnO6 octahedra, and an edgeedge with one SiO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.28–2.47 Å. In the fourth 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 2.31–2.49 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 SiO4 tetrahedra and an edgeedge with one NaO5 trigonal bipyramid. There are a spread of Sn–O bond distances ranging from 2.06–2.12 Å. In the second Sn site, Sn is bonded to six O atoms to form SnO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Sn–O bond distances ranging from 2.05–2.10 Å. There are six inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent SnO6 octahedra, corners with two SiO4 tetrahedra, and a cornercorner with one NaO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 48–49°. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent SnO6 octahedra, corners with two SiO4 tetrahedra, and a cornercorner with one NaO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 48–49°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent SnO6 octahedra, corners with two equivalent SiO4 tetrahedra, and corners with four equivalent NaO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 46°. There is two shorter (1.62 Å) and two longer (1.66 Å) Si–O bond length. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent SnO6 octahedra and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 47°. There is two shorter (1.62 Å) and two longer (1.66 Å) Si–O bond length. In the fifth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three SnO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 37–48°. There are a spread of Si–O bond distances ranging from 1.62–1.69 Å. In the sixth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three SnO6 octahedra, a cornercorner with one SiO4 tetrahedra, and an edgeedge with one NaO5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 38–49°. There is three shorter (1.63 Å) and one longer (1.69 Å) Si–O bond length. There are seventeen inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to one Na and two Si atoms. In the second O site, O is bonded in a 3-coordinate geometry to one Na and two Si atoms. In the third O site, O is bonded in a 4-coordinate geometry to two equivalent Na, one Sn, and one Si atom. In the fourth O site, O is bonded in a 4-coordinate geometry to two equivalent Na, one Sn, and one Si atom. In the fifth O site, O is bonded in a distorted trigonal planar geometry to one Na, one Sn, and one Si atom. In the sixth O site, O is bonded in a 3-coordinate geometry to one Na, one Sn, and one Si atom. In the seventh O site, O is bonded in a distorted trigonal planar geometry to one Na, one Sn, and one Si atom. In the eighth O site, O is bonded in a distorted trigonal planar geometry to one Na, one Sn, and one Si atom. In the ninth O site, O is bonded in a distorted trigonal planar geometry to one Na and two Si atoms. In the tenth O site, O is bonded in a distorted trigonal planar geometry to one Na and two Si atoms. In the eleventh O site, O is bonded in a 3-coordinate geometry to one Na, one Sn, and one Si atom. In the twelfth O site, O is bonded in a 3-coordinate geometry to one Na, one Sn, and one Si atom. In the thirteenth O site, O is bonded in a distorted T-shaped geometry to one Na, one Sn, and one Si atom. In the fourteenth O site, O is bonded in a distorted T-shaped geometry to one Na, one Sn, and one Si atom. In the fifteenth O site, O is bonded in a distorted trigonal planar geometry to one Na, one Sn, and one Si atom. In the sixteenth O site, O is bonded in a distorted trigonal planar geometry to one Na, one Sn, and one Si atom. In the seventeenth O site, O is bonded in a bent 120 degrees geometry to two Na atoms.

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2020-04-30. Materials Data on Na4Si5Sn2O17 by Materials Project. https://doi.org/10.17188/1741609

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36 MATERIALS SCIENCE↗