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DOE OSTI · 1655780

Materials Data on Ba2Fe4Bi2O11 by Materials Project

Abstract

Bi2Ba2Fe4O11 crystallizes in the tetragonal P4mm 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 distorted BaO12 cuboctahedra that share corners with four equivalent BaO12 cuboctahedra, faces with four equivalent BaO12 cuboctahedra, faces with four equivalent FeO6 octahedra, and faces with four equivalent FeO5 square pyramids. There are a spread of Ba–O bond distances ranging from 2.82–3.24 Å. In the second Ba2+ site, Ba2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are four shorter (2.63 Å) and four longer (2.92 Å) Ba–O bond lengths. There are four inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with five FeO6 octahedra, a cornercorner with one FeO5 square pyramid, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–15°. There are a spread of Fe–O bond distances ranging from 2.00–2.13 Å. In the second Fe3+ site, Fe3+ is bonded to five O2- atoms to form FeO5 square pyramids that share a cornercorner with one FeO6 octahedra, corners with four equivalent FeO5 square pyramids, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are one shorter (2.00 Å) and four longer (2.01 Å) Fe–O bond lengths. In the third Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with five FeO6 octahedra and a cornercorner with one FeO5 square pyramid. The corner-sharing octahedra tilt angles range from 0–15°. There are a spread of Fe–O bond distances ranging from 1.96–2.08 Å. In the fourth Fe3+ site, Fe3+ is bonded to five O2- atoms to form distorted FeO5 square pyramids that share a cornercorner with one FeO6 octahedra and corners with four equivalent FeO5 square pyramids. The corner-sharing octahedral tilt angles are 0°. There is one shorter (1.88 Å) and four longer (2.04 Å) Fe–O bond length. There are two inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.45 Å) and four longer (2.85 Å) Bi–O bond lengths. In the second Bi3+ site, Bi3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.45 Å) and four longer (2.85 Å) Bi–O bond lengths. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Ba2+ and two equivalent Fe3+ atoms to form distorted OBa2Fe2 trigonal pyramids that share corners with six equivalent OBa4Fe2 octahedra, corners with four equivalent OBa2Fe2 trigonal pyramids, an edgeedge with one OBa4Fe2 octahedra, and edges with four equivalent OBa2Fe2 trigonal pyramids. The corner-sharing octahedra tilt angles range from 6–62°. In the second O2- site, O2- is bonded to four Ba2+ and two equivalent Fe3+ atoms to form distorted OBa4Fe2 octahedra that share corners with six OBa4Fe2 octahedra, corners with six equivalent OBa2Fe2 trigonal pyramids, edges with two equivalent OBa4Fe2 octahedra, an edgeedge with one OBa2Fe2 trigonal pyramid, and faces with six OBa4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 16–55°. In the third O2- site, O2- is bonded in a distorted see-saw-like geometry to two equivalent Fe3+ and two equivalent Bi3+ atoms. In the fourth O2- site, O2- is bonded to four equivalent Ba2+ and two Fe3+ atoms to form a mixture of distorted face, edge, and corner-sharing OBa4Fe2 octahedra. The corner-sharing octahedra tilt angles range from 12–55°. In the fifth O2- site, O2- is bonded in a distorted linear geometry to two Fe3+ and four equivalent Bi3+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Fe3+, and two equivalent Bi3+ atoms. In the seventh O2- site, O2- is bonded in a distorted linear geometry to two Fe3+ and four equivalent Bi3+ atoms.

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2020-04-30. Materials Data on Ba2Fe4Bi2O11 by Materials Project. https://doi.org/10.17188/1655780

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