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DOE OSTI · 1673128

Materials Data on Sr4Fe6Bi7PbO24 by Materials Project

Abstract

Sr4Fe6PbBi7O24 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are three inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 5-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.44–2.99 Å. In the second Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.51–3.03 Å. In the third Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to eight O2- atoms. There are four shorter (2.48 Å) and four longer (2.86 Å) Sr–O bond lengths. There are six inequivalent Fe+2.83+ sites. In the first Fe+2.83+ site, Fe+2.83+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share a cornercorner with one BiO6 octahedra and corners with five FeO6 octahedra. The corner-sharing octahedra tilt angles range from 0–19°. There are a spread of Fe–O bond distances ranging from 1.95–2.29 Å. In the second Fe+2.83+ site, Fe+2.83+ is bonded to six O2- atoms to form distorted FeO6 octahedra that share a cornercorner with one PbO6 octahedra and corners with five FeO6 octahedra. The corner-sharing octahedra tilt angles range from 0–19°. There are five shorter (1.95 Å) and one longer (2.29 Å) Fe–O bond lengths. In the third Fe+2.83+ site, Fe+2.83+ 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°. All Fe–O bond lengths are 1.95 Å. In the fourth Fe+2.83+ site, Fe+2.83+ 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°. All Fe–O bond lengths are 1.95 Å. In the fifth Fe+2.83+ site, Fe+2.83+ is bonded to six O2- atoms to form distorted 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 0–18°. There are a spread of Fe–O bond distances ranging from 1.94–2.21 Å. In the sixth Fe+2.83+ site, Fe+2.83+ is bonded to six O2- atoms to form distorted 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 0–18°. There are a spread of Fe–O bond distances ranging from 1.95–2.21 Å. Pb2+ is bonded to six O2- atoms to form PbO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with four equivalent PbO6 octahedra, and edges with eight BiO6 octahedra. The corner-sharing octahedra tilt angles range from 0–12°. There are one shorter (2.51 Å) and five longer (2.73 Å) Pb–O bond lengths. There are six inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to six O2- atoms to form BiO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with four equivalent BiO6 octahedra, edges with four equivalent PbO6 octahedra, and edges with four equivalent BiO6 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. There are a spread of Bi–O bond distances ranging from 2.32–2.73 Å. In the second Bi3+ site, Bi3+ is bonded to six O2- atoms to form distorted BiO6 octahedra that share corners with four equivalent BiO6 octahedra, edges with two equivalent PbO6 octahedra, and edges with six BiO6 octahedra. The corner-sharing octahedra tilt angles range from 5–14°. There are a spread of Bi–O bond distances ranging from 2.06–2.90 Å. In the third Bi3+ site, Bi3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.47 Å) and four longer (2.75 Å) Bi–O bond lengths. In the fourth Bi3+ site, Bi3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.47 Å) and four longer (2.75 Å) Bi–O bond lengths. In the fifth Bi3+ site, Bi3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.45 Å) and four longer (2.74 Å) Bi–O bond lengths. In the sixth Bi3+ site, Bi3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.45 Å) and four longer (2.74 Å) Bi–O bond lengths. There are fifteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sr2+, two Fe+2.83+, and two Bi3+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Sr2+ and two Fe+2.83+ atoms. In the third O2- site, O2- is bonded to five Bi3+ atoms to form distorted OBi5 square pyramids that share a cornercorner with one OSr4FeBi octahedra, corners with four equivalent OBi5 square pyramids, and edges with eight OSrBi4Pb octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth O2- site, O2- is bonded to one Sr2+, one Pb2+, and four equivalent Bi3+ atoms to form OSrBi4Pb octahedra that share corners with five OSr4FePb octahedra, edges with four OSrBi3Pb2 octahedra, and edges with four equivalent OBi5 square pyramids. The corner-sharing octahedra tilt angles range from 0–5°. In the fifth O2- site, O2- is bonded to one Sr2+, two equivalent Pb2+, and three Bi3+ atoms to form distorted OSrBi3Pb2 octahedra that share corners with four equivalent OSrBi3Pb2 octahedra, edges with ten OSrBi4Pb octahedra, and edges with two equivalent OBi5 square pyramids. The corner-sharing octahedra tilt angles range from 10–12°. The O–Sr bond length is 2.44 Å. The O–Bi bond length is 2.90 Å. In the sixth O2- site, O2- is bonded to one Sr2+, two equivalent Pb2+, and three Bi3+ atoms to form distorted OSrBi3Pb2 octahedra that share corners with four equivalent OSrBi3Pb2 octahedra, edges with ten OSrBi4Pb octahedra, and edges with two equivalent OBi5 square pyramids. The corner-sharing octahedra tilt angles range from 10–12°. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two Fe+2.83+ and four Bi3+ atoms. In the eighth O2- site, O2- is bonded in a 6-coordinate geometry to two Fe+2.83+ and four Bi3+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two Fe+2.83+ and four Bi3+ atoms. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to two Fe+2.83+ and four Bi3+ atoms. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to two Fe+2.83+ and two Bi3+ atoms. In the twelfth O2- site, O2- is bonded to four equivalent Sr2+, one Fe+2.83+, and one Bi3+ atom to form distorted OSr4FeBi octahedra that share corners with four equivalent OSr4FeBi octahedra, a cornercorner with one OBi5 square pyramid, and edges with eight OSr4FePb octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the thirteenth O2- site, O2- is bonded to four equivalent Sr2+, one Fe+2.83+, and one Pb2+ atom to form distorted OSr4FePb octahedra that share corners with five OSrBi4Pb octahedra and edges with eight OSr4FeBi octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the fourteenth O2- site, O2- is bonded in a 1-coordinate geometry to four Sr2+ and one Bi3+ atom. The O–Bi bond length is 2.06 Å. In the fifteenth O2- site, O2- is bonded in a 1-coordinate geometry to four Sr2+ and one Bi3+ atom.

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2020-04-30. Materials Data on Sr4Fe6Bi7PbO24 by Materials Project. https://doi.org/10.17188/1673128

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