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DOE OSTI · 1291640

Materials Data on Sr2U4O11 by Materials Project

Abstract

Sr2U4O11 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a distorted hexagonal planar geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.40–2.52 Å. In the second Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.44–2.60 Å. There are four inequivalent U+4.50+ sites. In the first U+4.50+ site, U+4.50+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of U–O bond distances ranging from 2.27–2.39 Å. In the second U+4.50+ site, U+4.50+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of U–O bond distances ranging from 2.19–2.52 Å. In the third U+4.50+ site, U+4.50+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of U–O bond distances ranging from 2.12–2.50 Å. In the fourth U+4.50+ site, U+4.50+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of U–O bond distances ranging from 2.21–2.40 Å. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded to one Sr2+ and three U+4.50+ atoms to form distorted OSrU3 tetrahedra that share corners with fifteen OSrU3 tetrahedra and edges with six OU4 tetrahedra. In the second O2- site, O2- is bonded to three Sr2+ and one U+4.50+ atom to form OSr3U tetrahedra that share corners with sixteen OSr3U tetrahedra and edges with four OSrU3 tetrahedra. In the third O2- site, O2- is bonded to two equivalent Sr2+ and two U+4.50+ atoms to form OSr2U2 tetrahedra that share corners with thirteen OSr3U tetrahedra and edges with five OSrU3 tetrahedra. In the fourth O2- site, O2- is bonded to one Sr2+ and three U+4.50+ atoms to form a mixture of corner and edge-sharing OSrU3 tetrahedra. In the fifth O2- site, O2- is bonded to four U+4.50+ atoms to form distorted OU4 tetrahedra that share corners with sixteen OSr3U tetrahedra and edges with six OSrU3 tetrahedra. In the sixth O2- site, O2- is bonded to one Sr2+ and three U+4.50+ atoms to form a mixture of distorted corner and edge-sharing OSrU3 tetrahedra. In the seventh O2- site, O2- is bonded to one Sr2+ and three U+4.50+ atoms to form OSrU3 tetrahedra that share corners with twelve OSrU3 tetrahedra and edges with six OSr2U2 tetrahedra. In the eighth O2- site, O2- is bonded to four U+4.50+ atoms to form distorted OU4 tetrahedra that share corners with fifteen OSrU3 tetrahedra and edges with six OSr2U2 tetrahedra. In the ninth O2- site, O2- is bonded to one Sr2+ and three U+4.50+ atoms to form OSrU3 tetrahedra that share corners with fifteen OSr3U tetrahedra and edges with six OSrU3 tetrahedra. In the tenth O2- site, O2- is bonded to two equivalent Sr2+ and two U+4.50+ atoms to form distorted OSr2U2 tetrahedra that share corners with fourteen OSrU3 tetrahedra and edges with six OU4 tetrahedra. In the eleventh O2- site, O2- is bonded to one Sr2+ and three U+4.50+ atoms to form a mixture of corner and edge-sharing OSrU3 tetrahedra.

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2020-04-30. Materials Data on Sr2U4O11 by Materials Project. https://doi.org/10.17188/1291640

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