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DOE OSTI · 1285569

Materials Data on Na6U5V2O23 by Materials Project

Abstract

Na6U5V2O23 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are six inequivalent Na1+ sites. In the first Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.47–3.02 Å. In the second Na1+ site, Na1+ is bonded to six O2- atoms to form distorted NaO6 octahedra that share corners with two equivalent UO6 octahedra, a cornercorner with one UO7 pentagonal bipyramid, and edges with two equivalent NaO6 octahedra. The corner-sharing octahedra tilt angles range from 58–61°. There are a spread of Na–O bond distances ranging from 2.37–2.75 Å. In the third Na1+ site, Na1+ is bonded to five O2- atoms to form distorted NaO5 square pyramids that share corners with two UO7 pentagonal bipyramids, corners with two equivalent NaO5 square pyramids, and corners with two equivalent VO4 tetrahedra. There are a spread of Na–O bond distances ranging from 2.44–2.73 Å. In the fourth Na1+ site, Na1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Na–O bond distances ranging from 2.35–2.71 Å. In the fifth Na1+ site, Na1+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.41–2.88 Å. In the sixth Na1+ site, Na1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Na–O bond distances ranging from 2.33–2.97 Å. There are five inequivalent U6+ sites. In the first U6+ site, U6+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of U–O bond distances ranging from 1.87–2.68 Å. In the second U6+ site, U6+ is bonded to seven O2- atoms to form distorted UO7 pentagonal bipyramids that share a cornercorner with one NaO6 octahedra, a cornercorner with one NaO5 square pyramid, corners with three equivalent VO4 tetrahedra, and an edgeedge with one UO6 octahedra. The corner-sharing octahedral tilt angles are 54°. There are a spread of U–O bond distances ranging from 1.86–2.37 Å. In the third U6+ site, U6+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of U–O bond distances ranging from 1.86–2.56 Å. In the fourth U6+ site, U6+ is bonded to seven O2- atoms to form distorted UO7 pentagonal bipyramids that share a cornercorner with one NaO5 square pyramid, corners with three equivalent VO4 tetrahedra, and an edgeedge with one UO6 octahedra. There are a spread of U–O bond distances ranging from 1.86–2.38 Å. In the fifth U6+ site, U6+ is bonded to six O2- atoms to form UO6 octahedra that share corners with two equivalent NaO6 octahedra and edges with two UO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 58–61°. There are a spread of U–O bond distances ranging from 1.87–2.27 Å. There are two inequivalent V5+ sites. In the first V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with three equivalent UO7 pentagonal bipyramids and corners with two equivalent NaO5 square pyramids. There are a spread of V–O bond distances ranging from 1.69–1.80 Å. In the second V5+ site, V5+ is bonded to four O2- atoms to form VO4 tetrahedra that share corners with three equivalent UO7 pentagonal bipyramids. There are a spread of V–O bond distances ranging from 1.67–1.78 Å. There are twenty-three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one U6+ atom. In the second O2- site, O2- is bonded in a trigonal planar geometry to three U6+ atoms. In the third O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+ and one U6+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one U6+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one U6+ atom. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Na1+ and two U6+ atoms. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, one U6+, and one V5+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Na1+ and one U6+ atom. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Na1+ and three U6+ atoms. In the tenth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Na1+ and one U6+ atom. In the eleventh O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+ and one V5+ atom. In the twelfth O2- site, O2- is bonded in a 1-coordinate geometry to two U6+ and one V5+ atom. In the thirteenth O2- site, O2- is bonded to one Na1+ and three U6+ atoms to form distorted corner-sharing ONaU3 trigonal pyramids. In the fourteenth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two U6+, and one V5+ atom. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to three Na1+ and one U6+ atom. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Na1+, two U6+, and one V5+ atom. In the seventeenth O2- site, O2- is bonded in a 3-coordinate geometry to two Na1+ and one V5+ atom. In the eighteenth O2- site, O2- is bonded in a 1-coordinate geometry to one Na1+, two U6+, and one V5+ atom. In the nineteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+ and one V5+ atom. In the twentieth O2- site, O2- is bonded to one Na1+ and three U6+ atoms to form distorted corner-sharing ONaU3 trigonal pyramids. In the twenty-first O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+ and one U6+ atom. In the twenty-second O2- site, O2- is bonded in a 1-coordinate geometry to two Na1+ and one U6+ atom. In the twenty-third O2- site, O2- is bonded in a 1-coordinate geometry to three Na1+ and one U6+ atom.

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2019-11-05. Materials Data on Na6U5V2O23 by Materials Project. https://doi.org/10.17188/1285569

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