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DOE OSTI · 1687209

Materials Data on Y4Si2NO8 by Materials Project

Abstract

Y4Si2NO8 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent Y sites. In the first Y site, Y is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Y–O bond distances ranging from 2.26–2.72 Å. In the second Y site, Y is bonded in a 8-coordinate geometry to one N and seven O atoms. The Y–N bond length is 2.41 Å. There are a spread of Y–O bond distances ranging from 2.24–3.04 Å. In the third Y site, Y is bonded to one N and six O atoms to form distorted YNO6 hexagonal pyramids that share corners with three SiNO3 tetrahedra, edges with two equivalent YO6 octahedra, and edges with two SiNO3 tetrahedra. The Y–N bond length is 2.42 Å. There are a spread of Y–O bond distances ranging from 2.25–2.58 Å. In the fourth Y site, Y is bonded to six O atoms to form distorted YO6 octahedra that share corners with five SiNO3 tetrahedra and edges with two equivalent YNO6 hexagonal pyramids. There are a spread of Y–O bond distances ranging from 2.25–2.41 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded to one N and three O atoms to form SiNO3 tetrahedra that share corners with two equivalent YNO6 hexagonal pyramids, corners with two equivalent YO6 octahedra, a cornercorner with one SiNO3 tetrahedra, and an edgeedge with one YNO6 hexagonal pyramid. The corner-sharing octahedra tilt angles range from 33–53°. The Si–N bond length is 1.70 Å. There are a spread of Si–O bond distances ranging from 1.64–1.67 Å. In the second Si site, Si is bonded to one N and three O atoms to form SiNO3 tetrahedra that share a cornercorner with one YNO6 hexagonal pyramid, corners with three equivalent YO6 octahedra, a cornercorner with one SiNO3 tetrahedra, and an edgeedge with one YNO6 hexagonal pyramid. The corner-sharing octahedra tilt angles range from 41–62°. The Si–N bond length is 1.71 Å. There is two shorter (1.65 Å) and one longer (1.68 Å) Si–O bond length. N is bonded to two Y and two Si atoms to form distorted NY2Si2 trigonal pyramids that share corners with three OY4 tetrahedra, corners with two equivalent OY3Si trigonal pyramids, and edges with two OY4 tetrahedra. There are eight inequivalent O sites. In the first O site, O is bonded to four Y atoms to form OY4 tetrahedra that share corners with five OY4 tetrahedra, a cornercorner with one NY2Si2 trigonal pyramid, edges with two OY4 tetrahedra, an edgeedge with one NY2Si2 trigonal pyramid, and an edgeedge with one OY3Si trigonal pyramid. In the second O site, O is bonded in a 4-coordinate geometry to three Y and one Si atom. In the third O site, O is bonded to four Y atoms to form OY4 tetrahedra that share corners with four OY4 tetrahedra, a cornercorner with one NY2Si2 trigonal pyramid, a cornercorner with one OY3Si trigonal pyramid, edges with two OY4 tetrahedra, and an edgeedge with one OY3Si trigonal pyramid. In the fourth O site, O is bonded to three Y and one Si atom to form distorted OY3Si tetrahedra that share corners with five OY4 tetrahedra, a cornercorner with one NY2Si2 trigonal pyramid, an edgeedge with one NY2Si2 trigonal pyramid, and an edgeedge with one OY3Si trigonal pyramid. In the fifth O site, O is bonded in a 3-coordinate geometry to three Y and one Si atom. In the sixth O site, O is bonded in a 4-coordinate geometry to three Y and one Si atom. In the seventh O site, O is bonded in a 4-coordinate geometry to three Y and one Si atom. In the eighth O site, O is bonded to three Y and one Si atom to form distorted OY3Si trigonal pyramids that share a cornercorner with one OY4 tetrahedra, corners with two equivalent NY2Si2 trigonal pyramids, and edges with three OY4 tetrahedra.

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2020-04-29. Materials Data on Y4Si2NO8 by Materials Project. https://doi.org/10.17188/1687209

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