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DOE OSTI · 1283228

Materials Data on Na3Sm17Si12(O25F)2 by Materials Project

Abstract

Na3Sm17Si12(O25F)2 crystallizes in the trigonal P3 space group. The structure is three-dimensional. there are three inequivalent Na sites. In the first Na site, Na is bonded in a 6-coordinate geometry to six O atoms. There are three shorter (2.46 Å) and three longer (2.57 Å) Na–O bond lengths. In the second Na site, Na is bonded in a 9-coordinate geometry to six O atoms. There are three shorter (2.48 Å) and three longer (2.57 Å) Na–O bond lengths. In the third Na site, Na is bonded in a 6-coordinate geometry to six O atoms. There are three shorter (2.47 Å) and three longer (2.60 Å) Na–O bond lengths. There are nine inequivalent Sm sites. In the first Sm site, Sm is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Sm–O bond distances ranging from 2.27–2.73 Å. In the second Sm site, Sm is bonded to six O and one F atom to form distorted SmO6F pentagonal bipyramids that share corners with four SmO6F pentagonal bipyramids, corners with four SiO4 tetrahedra, and an edgeedge with one SiO4 tetrahedra. There are a spread of Sm–O bond distances ranging from 2.30–2.58 Å. The Sm–F bond length is 2.43 Å. In the third Sm site, Sm is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Sm–O bond distances ranging from 2.34–2.82 Å. In the fourth Sm site, Sm is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Sm–O bond distances ranging from 2.44–2.82 Å. In the fifth Sm site, Sm is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Sm–O bond distances ranging from 2.40–2.76 Å. In the sixth Sm site, Sm is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Sm–O bond distances ranging from 2.28–2.62 Å. In the seventh Sm site, Sm is bonded to six O and one F atom to form distorted SmO6F pentagonal bipyramids that share corners with four SmO6F pentagonal bipyramids, corners with four SiO4 tetrahedra, and an edgeedge with one SiO4 tetrahedra. There are a spread of Sm–O bond distances ranging from 2.31–2.57 Å. The Sm–F bond length is 2.44 Å. In the eighth Sm site, Sm is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Sm–O bond distances ranging from 2.41–2.83 Å. In the ninth Sm site, Sm is bonded in a 9-coordinate geometry to nine O atoms. There are a spread of Sm–O bond distances ranging from 2.38–2.84 Å. There are four 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 SmO6F pentagonal bipyramid. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three SmO6F pentagonal bipyramids and an edgeedge with one SmO6F pentagonal bipyramid. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one SmO6F pentagonal bipyramid. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three SmO6F pentagonal bipyramids and an edgeedge with one SmO6F pentagonal bipyramid. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. There are eighteen inequivalent O sites. In the first O site, O is bonded in a trigonal planar geometry to three equivalent Sm atoms. In the second O site, O is bonded in a 1-coordinate geometry to three Sm and one Si atom. In the third O site, O is bonded in a 1-coordinate geometry to three Sm and one Si atom. In the fourth O site, O is bonded in a 1-coordinate geometry to three Sm and one Si atom. In the fifth O site, O is bonded in a 1-coordinate geometry to two Sm and one Si atom. In the sixth O site, O is bonded in a 4-coordinate geometry to three Sm and one Si atom. In the seventh O site, O is bonded in a 4-coordinate geometry to one Na, two Sm, and one Si atom. In the eighth O site, O is bonded in a 1-coordinate geometry to three Sm and one Si atom. In the ninth O site, O is bonded in a 4-coordinate geometry to one Na, two Sm, and one Si atom. In the tenth O site, O is bonded in a trigonal planar geometry to three equivalent Sm atoms. In the eleventh O site, O is bonded in a 1-coordinate geometry to two Sm and one Si atom. In the twelfth O site, O is bonded in a 1-coordinate geometry to two Sm and one Si atom. In the thirteenth O site, O is bonded in a 1-coordinate geometry to three Sm and one Si atom. In the fourteenth O site, O is bonded in a 1-coordinate geometry to three Sm and one Si atom. In the fifteenth O site, O is bonded in a 1-coordinate geometry to one Na, two Sm, and one Si atom. In the sixteenth O site, O is bonded in a 4-coordinate geometry to one Na, two Sm, and one Si atom. In the seventeenth O site, O is bonded in a 4-coordinate geometry to one Na, two Sm, and one Si atom. In the eighteenth O site, O is bonded in a 4-coordinate geometry to one Na, two Sm, and one Si atom. There are two inequivalent F sites. In the first F site, F is bonded in a trigonal planar geometry to three equivalent Sm atoms. In the second F site, F is bonded in a trigonal planar geometry to three equivalent Sm atoms.

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2020-05-29. Materials Data on Na3Sm17Si12(O25F)2 by Materials Project. https://doi.org/10.17188/1283228

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