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DOE OSTI · 1759240

Materials Data on CaYMg14O16 by Materials Project

Abstract

CaMg14YO16 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ca is bonded to six O atoms to form CaO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.21 Å) and four longer (2.29 Å) Ca–O bond lengths. There are five inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with two equivalent MgO6 octahedra, corners with two equivalent YO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.09–2.21 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent CaO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are a spread of Mg–O bond distances ranging from 2.16–2.23 Å. In the third Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent CaO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are a spread of Mg–O bond distances ranging from 2.16–2.23 Å. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent YO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Mg–O bond distances ranging from 2.08–2.30 Å. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six equivalent MgO6 octahedra, an edgeedge with one CaO6 octahedra, an edgeedge with one YO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–7°. There are a spread of Mg–O bond distances ranging from 2.16–2.23 Å. Y is bonded to six O atoms to form YO6 octahedra that share corners with two equivalent YO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.21 Å) and four longer (2.26 Å) Y–O bond lengths. There are ten inequivalent O sites. In the first O site, O is bonded to one Ca and five Mg atoms to form a mixture of edge and corner-sharing OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the second O site, O is bonded to five Mg and one Y atom to form a mixture of edge and corner-sharing OYMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. Both O–Mg bond lengths are 2.21 Å. In the third O site, O is bonded to five Mg and one Y atom to form a mixture of edge and corner-sharing OYMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are two shorter (2.21 Å) and two longer (2.23 Å) O–Mg bond lengths. In the fourth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 2–5°. In the fifth O site, O is bonded to two equivalent Ca and four Mg atoms to form OCa2Mg4 octahedra that share corners with six OCa2Mg4 octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the sixth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OCa2Mg4 octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the seventh O site, O is bonded to four equivalent Mg and two equivalent Y atoms to form OY2Mg4 octahedra that share corners with six OMg6 octahedra and edges with twelve OYMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the eighth O site, O is bonded to one Ca and five Mg atoms to form a mixture of edge and corner-sharing OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. Both O–Mg bond lengths are 2.16 Å. In the ninth O site, O is bonded to five Mg and one Y atom to form a mixture of edge and corner-sharing OYMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. The O–Mg bond length is 2.12 Å. In the tenth O site, O is bonded to five Mg and one Y atom to form a mixture of edge and corner-sharing OYMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of O–Mg bond distances ranging from 2.12–2.23 Å.

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2020-09-03. Materials Data on CaYMg14O16 by Materials Project. https://doi.org/10.17188/1759240

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36 MATERIALS SCIENCE↗