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DOE OSTI · 1653391

Materials Data on CsMg6WO8 by Materials Project

Abstract

CsMg6WO8 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Cs1+ is bonded to six O2- atoms to form CsO6 octahedra that share corners with two equivalent WO6 octahedra, corners with four equivalent CsO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.32 Å) and two longer (2.58 Å) Cs–O bond lengths. There are three inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with four equivalent CsO6 octahedra, and edges with eight equivalent MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.32 Å) and two longer (2.34 Å) Mg–O bond lengths. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with four equivalent WO6 octahedra, and edges with eight equivalent MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Mg–O bond lengths are 2.32 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six equivalent MgO6 octahedra, edges with two equivalent CsO6 octahedra, edges with two equivalent WO6 octahedra, and edges with eight MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–13°. There are a spread of Mg–O bond distances ranging from 2.31–2.35 Å. W3+ is bonded to six O2- atoms to form WO6 octahedra that share corners with two equivalent CsO6 octahedra, corners with four equivalent WO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.08 Å) and four longer (2.32 Å) W–O bond lengths. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to one Cs1+, four equivalent Mg2+, and one W3+ atom to form OCsMg4W octahedra that share corners with six equivalent OCsMg4W octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–13°. In the second O2- site, O2- is bonded to six Mg2+ atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OCsMg4W octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the third O2- site, O2- is bonded to two equivalent Cs1+ and four Mg2+ atoms to form OCs2Mg4 octahedra that share corners with six OCs2Mg4 octahedra and edges with twelve OCsMg4W octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth O2- site, O2- is bonded to four Mg2+ and two equivalent W3+ atoms to form OMg4W2 octahedra that share corners with six OCs2Mg4 octahedra and edges with twelve OCsMg4W octahedra. The corner-sharing octahedral tilt angles are 0°. In the fifth O2- site, O2- is bonded to two equivalent Cs1+ and four Mg2+ atoms to form OCs2Mg4 octahedra that share corners with six OMg4W2 octahedra and edges with twelve OCsMg4W octahedra. The corner-sharing octahedral tilt angles are 0°. Both O–Mg bond lengths are 2.31 Å.

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2020-05-03. Materials Data on CsMg6WO8 by Materials Project. https://doi.org/10.17188/1653391

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