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DOE OSTI · 1206858

Materials Data on NbFeO4 by Materials Project

Abstract

FeNbO4 is zeta iron carbide-derived structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with four NbO6 octahedra, corners with four FeO6 octahedra, and edges with two equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 45–59°. There are a spread of Nb–O bond distances ranging from 1.92–2.26 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with four NbO6 octahedra, corners with four FeO6 octahedra, and edges with two equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 45–58°. There are a spread of Nb–O bond distances ranging from 1.92–2.26 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with four NbO6 octahedra, corners with four FeO6 octahedra, and edges with two equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 45–58°. There are a spread of Nb–O bond distances ranging from 1.92–2.26 Å. In the fourth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted NbO6 octahedra that share corners with four NbO6 octahedra, corners with four FeO6 octahedra, and edges with two equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 45–59°. There are a spread of Nb–O bond distances ranging from 1.92–2.26 Å. 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 four NbO6 octahedra, corners with four FeO6 octahedra, and edges with two equivalent NbO6 octahedra. The corner-sharing octahedra tilt angles range from 45–55°. There are a spread of Fe–O bond distances ranging from 1.95–2.15 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four NbO6 octahedra, corners with four FeO6 octahedra, and edges with two equivalent NbO6 octahedra. The corner-sharing octahedra tilt angles range from 45–55°. There are a spread of Fe–O bond distances ranging from 1.95–2.15 Å. In the third Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four NbO6 octahedra, corners with four FeO6 octahedra, and edges with two equivalent NbO6 octahedra. The corner-sharing octahedra tilt angles range from 45–55°. There are a spread of Fe–O bond distances ranging from 1.95–2.15 Å. In the fourth Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four NbO6 octahedra, corners with four FeO6 octahedra, and edges with two equivalent NbO6 octahedra. The corner-sharing octahedra tilt angles range from 45–55°. There are a spread of Fe–O bond distances ranging from 1.95–2.15 Å. There are sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Nb5+ and two Fe3+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one Fe3+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Nb5+ and two Fe3+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one Fe3+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one Fe3+ atom. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Nb5+ and two Fe3+ atoms. In the seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one Fe3+ atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Nb5+ and two Fe3+ atoms. In the ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one Fe3+ atom. In the tenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Nb5+ and two Fe3+ atoms. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one Fe3+ atom. In the twelfth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Nb5+ and two Fe3+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Nb5+ and two Fe3+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one Fe3+ atom. In the fifteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Nb5+ and one Fe3+ atom. In the sixteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Nb5+ and two Fe3+ atoms.

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2020-08-03. Materials Data on NbFeO4 by Materials Project. https://doi.org/10.17188/1206858

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36 MATERIALS SCIENCE↗