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DOE OSTI · 1737127

Materials Data on Na5Zr2Si12O37 by Materials Project

Abstract

(Na5Zr2(SiO3)12)2O2 crystallizes in the monoclinic C2 space group. The structure is three-dimensional and consists of two water molecules and one Na5Zr2(SiO3)12 framework. In the Na5Zr2(SiO3)12 framework, there are three inequivalent Na sites. In the first Na site, Na is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Na–O bond distances ranging from 2.34–2.83 Å. In the second Na site, Na is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Na–O bond distances ranging from 2.36–2.77 Å. In the third Na site, Na is bonded to eight O atoms to form distorted NaO8 hexagonal bipyramids that share corners with two equivalent SiO4 tetrahedra, edges with two equivalent ZrO6 octahedra, and edges with four SiO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.40–2.93 Å. Zr is bonded to six O atoms to form ZrO6 octahedra that share corners with six SiO4 tetrahedra and an edgeedge with one NaO8 hexagonal bipyramid. There are a spread of Zr–O bond distances ranging from 2.07–2.14 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 a cornercorner with one ZrO6 octahedra, corners with two SiO4 tetrahedra, and an edgeedge with one NaO8 hexagonal bipyramid. The corner-sharing octahedral tilt angles are 27°. There are a spread of Si–O bond distances ranging from 1.62–1.64 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one ZrO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 27°. There is three shorter (1.63 Å) and one longer (1.64 Å) Si–O bond length. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one ZrO6 octahedra, corners with two SiO4 tetrahedra, and an edgeedge with one NaO8 hexagonal bipyramid. The corner-sharing octahedral tilt angles are 32°. There are a spread of Si–O bond distances ranging from 1.62–1.64 Å. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one ZrO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 32°. There is three shorter (1.63 Å) and one longer (1.64 Å) Si–O bond length. In the fifth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one ZrO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 28°. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. In the sixth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one NaO8 hexagonal bipyramid, a cornercorner with one ZrO6 octahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 25°. All Si–O bond lengths are 1.63 Å. There are twenty inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to one Na and two equivalent Si atoms. In the second O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the third O site, O is bonded in a distorted T-shaped geometry to one Na and two equivalent Si atoms. In the fourth O site, O is bonded in a linear geometry to two equivalent Si atoms. In the fifth O site, O is bonded in a 2-coordinate geometry to one Na and two Si atoms. In the sixth O site, O is bonded in a 2-coordinate geometry to one Na and two Si atoms. In the seventh O site, O is bonded in a distorted bent 120 degrees geometry to one Na and one Si atom. In the eighth O site, O is bonded in a distorted bent 120 degrees geometry to one Na and one Si atom. In the ninth O site, O is bonded in a 2-coordinate geometry to two Na, one Zr, and one Si atom. In the tenth O site, O is bonded in a 2-coordinate geometry to one Na, one Zr, and one Si atom. In the eleventh O site, O is bonded in a distorted T-shaped geometry to one Na and two Si atoms. In the twelfth O site, O is bonded in a distorted T-shaped geometry to one Na and two Si atoms. In the thirteenth O site, O is bonded in a distorted bent 150 degrees geometry to two Na, one Zr, and one Si atom. In the fourteenth O site, O is bonded in a 2-coordinate geometry to one Na, one Zr, and one Si atom. In the fifteenth O site, O is bonded in a 2-coordinate geometry to one Na, one Zr, and one Si atom. In the sixteenth O site, O is bonded in a 2-coordinate geometry to one Na, one Zr, and one Si atom. In the seventeenth O site, O is bonded in a distorted bent 150 degrees geometry to one Na and one Si atom. In the eighteenth O site, O is bonded in a distorted bent 150 degrees geometry to one Na and one Si atom. In the nineteenth O site, O is bonded in a single-bond geometry to one Si atom. In the twentieth O site, O is bonded in a bent 120 degrees geometry to one Na and one Si atom.

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2020-04-29. Materials Data on Na5Zr2Si12O37 by Materials Project. https://doi.org/10.17188/1737127

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36 MATERIALS SCIENCE↗