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DOE OSTI · 1320963

Materials Data on Ca2TaFeO6 by Materials Project

Abstract

Ca2TaFeO6 is Orthorhombic Perovskite-derived structured and crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.32–2.76 Å. In the second Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.37–2.71 Å. Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with two equivalent TaO6 octahedra and corners with four equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 29–30°. There are a spread of Ta–O bond distances ranging from 1.98–2.02 Å. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two equivalent FeO6 octahedra and corners with four equivalent TaO6 octahedra. The corner-sharing octahedra tilt angles range from 29–30°. There are a spread of Fe–O bond distances ranging from 2.02–2.10 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three Ca2+, one Ta5+, and one Fe3+ atom. In the second O2- site, O2- is bonded in a 5-coordinate geometry to three Ca2+, one Ta5+, and one Fe3+ atom. In the third O2- site, O2- is bonded to two Ca2+ and two equivalent Ta5+ atoms to form distorted corner-sharing OCa2Ta2 tetrahedra. In the fourth O2- site, O2- is bonded to two Ca2+ and two equivalent Fe3+ atoms to form distorted corner-sharing OCa2Fe2 tetrahedra.

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2020-07-15. Materials Data on Ca2TaFeO6 by Materials Project. https://doi.org/10.17188/1320963

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36 MATERIALS SCIENCE↗