DOI: 10.17188/1284755
title: Materials Data on Ba3HoUFeO9 by Materials Project

description: Ba3UHoFeO9 crystallizes in the trigonal P3m1 space group. The structure is three-dimensional. there are six inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to nine O2- atoms. There are three shorter (2.73 Å) and six longer (3.01 Å) Ba–O bond lengths. In the second Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with six equivalent BaO12 cuboctahedra, faces with three equivalent UO6 octahedra, and faces with four FeO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.89–3.16 Å. In the third Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are three shorter (2.64 Å) and three longer (2.65 Å) Ba–O bond lengths. In the fourth Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to nine O2- atoms. There are three shorter (2.76 Å) and six longer (3.00 Å) Ba–O bond lengths. In the fifth Ba2+ site, Ba2+ is bonded in a distorted hexagonal planar geometry to six O2- atoms. There are three shorter (2.65 Å) and three longer (2.68 Å) Ba–O bond lengths. In the sixth Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to nine O2- atoms. There are three shorter (2.76 Å) and six longer (3.01 Å) Ba–O bond lengths. There are two inequivalent U6+ sites. In the first U6+ site, U6+ is bonded in an octahedral geometry to six O2- atoms. There are three shorter (2.08 Å) and three longer (2.09 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 three equivalent FeO6 octahedra and faces with three equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 1°. There are three shorter (2.04 Å) and three longer (2.15 Å) U–O bond lengths. There are two inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded in a 3-coordinate geometry to three equivalent O2- atoms. All Ho–O bond lengths are 2.17 Å. In the second Ho3+ site, Ho3+ is bonded in a 3-coordinate geometry to three equivalent O2- atoms. All Ho–O bond lengths are 2.18 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent FeO6 octahedra and a faceface with one BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 6°. There are three shorter (1.97 Å) and three longer (2.24 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 three equivalent UO6 octahedra, corners with three equivalent FeO6 octahedra, and faces with three equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–6°. There are three shorter (2.03 Å) and three longer (2.07 Å) Fe–O bond lengths. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to four Ba2+ and one U6+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to four Ba2+ and one U6+ atom. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ba2+, one Ho3+, and two Fe3+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to three Ba2+, one U6+, and one Fe3+ atom. In the fifth O2- site, O2- is bonded in a 5-coordinate geometry to four Ba2+ and one U6+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+, one Ho3+, and one Fe3+ atom.