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Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Sr3UFe2O9 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form distorted SrO12 cuboctahedra that share corners with two equivalent SrO12 cuboctahedra, faces with two equivalent SrO12 cuboctahedra, faces with two equivalent UO6 octahedra, and faces with six FeO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.72–3.12 Å. In the second Sr2+ site, Sr2+ is bonded in a 12-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.61–2.91 Å. U6+ is bonded to six O2- atoms to form UO6 octahedra that share corners with six FeO6 octahedra and faces with two equivalent SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 2°. There are a spread of U–O bond distances ranging from 2.07–2.09 Å. There are three inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with four equivalent UO6 octahedra, and faces with four equivalent SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. All Fe–O bond lengths are 2.04 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with four equivalent UO6 octahedra, and faces with two equivalent SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–2°. There are a spread of Fe–O bond distances ranging from 2.01–2.04 Å. In the third Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with six FeO6 octahedra and faces with four equivalent SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are four shorter (2.04 Å) and two longer (2.08 Å) Fe–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to four Sr2+ and two Fe3+ atoms to form a mixture of distorted face and corner-sharing OSr4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–54°. In the second O2- site, O2- is bonded in a distorted linear geometry to three Sr2+, one U6+, and one Fe3+ atom. In the third O2- site, O2- is bonded in a distorted linear geometry to four Sr2+, one U6+, and one Fe3+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Sr2+, one U6+, and one Fe3+ atom. In the fifth O2- site, O2- is bonded to four Sr2+ and two Fe3+ atoms to form a mixture of distorted face, edge, and corner-sharing OSr4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–54°.