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DOE OSTI · 1318804

Materials Data on FeO2 by Materials Project

Abstract

FeO2 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are twelve inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with three FeO4 tetrahedra and edges with four FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.85–2.11 Å. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with three equivalent FeO4 tetrahedra and edges with four FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.86–2.06 Å. In the third Fe site, Fe is bonded to four O atoms to form corner-sharing FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–56°. There are a spread of Fe–O bond distances ranging from 1.82–1.89 Å. In the fourth Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four FeO4 tetrahedra and edges with three FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.85–2.02 Å. In the fifth Fe site, Fe is bonded to four O atoms to form corner-sharing FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–60°. There are a spread of Fe–O bond distances ranging from 1.88–1.96 Å. In the sixth Fe site, Fe is bonded to four O atoms to form corner-sharing FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–56°. There are a spread of Fe–O bond distances ranging from 1.77–1.86 Å. In the seventh Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six FeO4 tetrahedra and edges with two equivalent FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.91–2.02 Å. In the eighth Fe site, Fe is bonded to four O atoms to form corner-sharing FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 52–55°. There are a spread of Fe–O bond distances ranging from 1.83–1.90 Å. In the ninth Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with five FeO4 tetrahedra and edges with three FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.86–2.14 Å. In the tenth Fe site, Fe is bonded to four O atoms to form corner-sharing FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 51–57°. There are a spread of Fe–O bond distances ranging from 1.82–1.93 Å. In the eleventh Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with three equivalent FeO4 tetrahedra and edges with four FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.87–2.06 Å. In the twelfth Fe site, Fe is bonded to four O atoms to form corner-sharing FeO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–58°. There are a spread of Fe–O bond distances ranging from 1.91–1.96 Å. There are twenty-four inequivalent O sites. In the first O site, O is bonded in a water-like geometry to two Fe atoms. In the second O site, O is bonded in a water-like geometry to two equivalent Fe atoms. In the third O site, O is bonded in a distorted T-shaped geometry to three Fe atoms. In the fourth O site, O is bonded in a distorted rectangular see-saw-like geometry to four Fe atoms. In the fifth O site, O is bonded in a water-like geometry to two Fe atoms. In the sixth O site, O is bonded in a trigonal planar geometry to three Fe atoms. In the seventh O site, O is bonded in a distorted trigonal planar geometry to three Fe atoms. In the eighth O site, O is bonded in a trigonal planar geometry to three Fe atoms. In the ninth O site, O is bonded in a distorted T-shaped geometry to three Fe atoms. In the tenth O site, O is bonded in a bent 120 degrees geometry to two Fe atoms. In the eleventh O site, O is bonded in a trigonal planar geometry to three Fe atoms. In the twelfth O site, O is bonded in a bent 120 degrees geometry to two Fe atoms. In the thirteenth O site, O is bonded in a distorted trigonal planar geometry to three Fe atoms. In the fourteenth O site, O is bonded in a distorted trigonal planar geometry to three Fe atoms. In the fifteenth O site, O is bonded in a trigonal planar geometry to three Fe atoms. In the sixteenth O site, O is bonded in a distorted trigonal planar geometry to three Fe atoms. In the seventeenth O site, O is bonded in a bent 120 degrees geometry to two Fe atoms. In the eighteenth O site, O is bonded in a bent 120 degrees geometry to two Fe atoms. In the nineteenth O site, O is bonded in a water-like geometry to two equivalent Fe atoms. In the twentieth O site, O is bonded in a distorted trigonal planar geometry to three Fe atoms. In the twenty-first O site, O is bonded in a distorted trigonal planar geometry to three Fe atoms. In the twenty-second O site, O is bonded in a distorted rectangular see-saw-like geometry to four Fe atoms. In the twenty-third O site, O is bonded in a trigonal planar geometry to three Fe atoms. In the twenty-fourth O site, O is bonded in a trigonal planar geometry to three Fe atoms.

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2020-08-03. Materials Data on FeO2 by Materials Project. https://doi.org/10.17188/1318804

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36 MATERIALS SCIENCE↗