Materials Data on Ba3UFe2O9 by Materials Project

Abstract

Ba3UFe2O9 is (Cubic) Perovskite-derived structured and crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with twelve BaO12 cuboctahedra, faces with six BaO12 cuboctahedra, faces with two equivalent UO6 octahedra, and faces with six FeO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.84–3.10 Å. In the second Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with twelve BaO12 cuboctahedra, faces with six BaO12 cuboctahedra, faces with three equivalent UO6 octahedra, and faces with five FeO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.77–3.14 Å. U6+ is bonded to six O2- atoms to form UO6 octahedra that share corners with six FeO6 octahedra and faces with eight BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are four shorter (2.09 Å) and two longer (2.10 Å) U–O bond lengths. 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 eight BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.06 Å) and four longer (2.09 Å) Fe–O bond lengths. 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 eight BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–2°. There are a spread of Fe–O bond distances ranging from 2.01–2.12 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 eight BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are four shorter (2.09 Å) and two longer (2.15 Å) Fe–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to four Ba2+ and two Fe3+ atoms to form a mixture of distorted corner and face-sharing OBa4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–55°. In the second O2- site, O2- is bonded in a distorted linear geometry to four Ba2+, one U6+, and one Fe3+ atom. In the third O2- site, O2- is bonded in a distorted linear geometry to four Ba2+, one U6+, and one Fe3+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to four equivalent Ba2+, one U6+, and one Fe3+ atom. In the fifth O2- site, O2- is bonded to four Ba2+ and two Fe3+ atoms to form a mixture of distorted edge, corner, and face-sharing OBa4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 0–55°.