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Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
TmFe2O4 is Aluminum carbonitride-like structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Tm3+ is bonded to six equivalent O2- atoms to form TmO6 octahedra that share corners with six equivalent FeO5 trigonal bipyramids and edges with six equivalent TmO6 octahedra. All Tm–O bond lengths are 2.26 Å. Fe+2.50+ is bonded to five O2- atoms to form FeO5 trigonal bipyramids that share corners with three equivalent TmO6 octahedra, corners with six equivalent FeO5 trigonal bipyramids, and edges with three equivalent FeO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 63°. There are a spread of Fe–O bond distances ranging from 1.99–2.18 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Fe+2.50+ atoms to form OFe4 trigonal pyramids that share corners with four equivalent OTm3Fe tetrahedra, corners with six equivalent OFe4 trigonal pyramids, and edges with three equivalent OFe4 trigonal pyramids. In the second O2- site, O2- is bonded to three equivalent Tm3+ and one Fe+2.50+ atom to form OTm3Fe tetrahedra that share corners with nine equivalent OTm3Fe tetrahedra, corners with four equivalent OFe4 trigonal pyramids, and edges with three equivalent OTm3Fe tetrahedra.
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations
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(FeO2)12Cl2 is Hydrophilite-derived structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional and consists of two chlorine molecules and one FeO2 framework. In the FeO2 framework, there are four inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form a mixture of corner and edge-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 48–50°. There are a spread of Fe–O bond distances ranging from 1.93–2.11 Å. In the second Fe site, Fe is bonded to six O atoms to form a mixture of corner and edge-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 48–51°. There are a spread of Fe–O bond distances ranging from 1.92–2.12 Å. In the third Fe site, Fe is bonded to six O atoms to form a mixture of corner and edge-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 48–50°. There are a spread of Fe–O bond distances ranging from 1.93–2.12 Å. In the fourth Fe site, Fe is bonded to six O atoms to form a mixture of corner and edge-sharing FeO6 octahedra. The corner-sharing octahedra tilt angles range from 48–51°. There are a spread of Fe–O bond distances ranging from 1.92–2.13 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to three Fe atoms. In the second O site, O is bonded in a distorted trigonal planar geometry to three Fe atoms. In the third O site, O is bonded in a distorted trigonal non-coplanar geometry to three Fe atoms. In the fourth O site, O is bonded in a distorted trigonal non-coplanar geometry to three Fe atoms. In the fifth O site, O is bonded in a distorted trigonal planar geometry to three Fe atoms. In the sixth O site, O is bonded in a distorted trigonal planar geometry to three Fe atoms. In the seventh O site, O is bonded in a distorted trigonal non-coplanar geometry to three Fe atoms. In the eighth O site, O is bonded in a distorted trigonal non-coplanar geometry to three Fe atoms.
(FeO2)3Fe3(SiO3)4 crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of one Fe3(SiO3)4 sheet oriented in the (0, 0, 1) direction and one FeO2 sheet oriented in the (0, 0, 1) direction. In the Fe3(SiO3)4 sheet, there are two inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four equivalent SiO4 tetrahedra and edges with six equivalent FeO6 octahedra. There are two shorter (1.96 Å) and four longer (2.10 Å) Fe–O bond lengths. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four equivalent SiO4 tetrahedra and edges with six FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.98–2.18 Å. Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three FeO6 octahedra and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. There is three shorter (1.62 Å) and one longer (1.69 Å) Si–O bond length. There are four inequivalent O sites. In the first O site, O is bonded in a rectangular see-saw-like geometry to three Fe and one Si atom. In the second O site, O is bonded in a distorted trigonal non-coplanar geometry to three Fe atoms. In the third O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the fourth O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the FeO2 sheet, there are two inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form edge-sharing FeO6 octahedra. There are four shorter (1.95 Å) and two longer (2.11 Å) Fe–O bond lengths. In the second Fe site, Fe is bonded to six O atoms to form edge-sharing FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 1.97–2.10 Å. There are two inequivalent O sites. In the first O site, O is bonded in a distorted trigonal non-coplanar geometry to three Fe atoms. In the second O site, O is bonded in a distorted trigonal non-coplanar geometry to three Fe atoms.
Al4(FeO4)3(FeO2)3 crystallizes in the monoclinic C2/m space group. The structure is two-dimensional and consists of one Al4(FeO4)3 sheet oriented in the (0, 0, 1) direction and one FeO2 sheet oriented in the (0, 0, 1) direction. In the Al4(FeO4)3 sheet, there are two inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four equivalent AlO4 tetrahedra and edges with six FeO6 octahedra. There are a spread of Fe–O bond distances ranging from 2.04–2.13 Å. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with four equivalent AlO4 tetrahedra and edges with six equivalent FeO6 octahedra. There are two shorter (1.95 Å) and four longer (2.10 Å) Fe–O bond lengths. Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with three FeO6 octahedra and corners with three equivalent AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 58–63°. There are a spread of Al–O bond distances ranging from 1.69–1.85 Å. There are four inequivalent O sites. In the first O site, O is bonded to three Fe and one Al atom to form a mixture of distorted corner and edge-sharing OAlFe3 tetrahedra. In the second O site, O is bonded in a trigonal non-coplanar geometry to three Fe atoms. In the third O site, O is bonded in a bent 150 degrees geometry to two equivalent Al atoms. In the fourth O site, O is bonded in a bent 150 degrees geometry to two equivalent Al atoms. In the FeO2 sheet, Fe is bonded to six O atoms to form distorted edge-sharing FeO6 octahedra. There are two shorter (1.94 Å) and four longer (2.07 Å) Fe–O bond lengths. There are two inequivalent O sites. In the first O site, O is bonded in a trigonal non-coplanar geometry to three equivalent Fe atoms. In the second O site, O is bonded in a trigonal non-coplanar geometry to three equivalent Fe atoms.
Abstract As the reaction product of subducted water and the iron core, FeO2 with more oxygen than hematite (Fe2O3) has been recently recognized as an important component in the D” layer just above the Earth's core-mantle boundary. Here, we report a new oxygen-excess phase (Mg, Fe)2O3+δ (0 < δ < 1, denoted as ‘OE-phase’). It forms at pressures greater than 40 gigapascal when (Mg, Fe)-bearing hydrous materials are heated over 1500 kelvin. The OE-phase is fully recoverable to ambient conditions for ex situ investigation using transmission electron microscopy, which indicates that the OE-phase contains ferric iron (Fe3+) as in Fe2O3 but holds excess oxygen through interactions between oxygen atoms. The new OE-phase provides strong evidence that H2O has extraordinary oxidation power at high pressure. Unlike the formation of pyrite-type FeO2Hx which usually requires saturated water, the OE-phase can be formed with under-saturated water at mid-mantle conditions, and is expected to be more ubiquitous at depths greater than 1000 km in the Earth's mantle. The emergence of oxygen-excess reservoirs out of primordial or subducted (Mg, Fe)-bearing hydrous materials may revise our view on the deep-mantle redox chemistry.