Materials Data on BaSr4U3O14 by Materials Project

Abstract

BaSr4U3O14 crystallizes in the orthorhombic Cmce space group. The structure is three-dimensional. Ba2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are four shorter (2.83 Å) and four longer (2.92 Å) Ba–O bond lengths. There are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.52–2.67 Å. In the second Sr2+ site, Sr2+ is bonded to seven O2- atoms to form distorted SrO7 pentagonal bipyramids that share corners with three UO6 octahedra and edges with three UO6 octahedra. The corner-sharing octahedra tilt angles range from 37–45°. There are a spread of Sr–O bond distances ranging from 2.47–2.68 Å. There are two inequivalent U6+ sites. In the first U6+ site, U6+ is bonded to six O2- atoms to form UO6 octahedra that share corners with four equivalent UO6 octahedra, corners with two equivalent SrO7 pentagonal bipyramids, and edges with two equivalent SrO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 44°. There are two shorter (1.96 Å) and four longer (2.16 Å) U–O bond lengths. In the second U6+ site, U6+ is bonded to six O2- atoms to form UO6 octahedra that share corners with two equivalent UO6 octahedra, corners with two equivalent SrO7 pentagonal bipyramids, and edges with two equivalent SrO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 44°. There are a spread of U–O bond distances ranging from 2.05–2.21 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, two Sr2+, and one U6+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two U6+ atoms. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sr2+ and one U6+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+, two Sr2+, and one U6+ atom.