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DOE OSTI · 1724040

Materials Data on KMg14BO15 by Materials Project

Abstract

KMg14BO15 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. K is bonded to six O atoms to form distorted KO6 octahedra that share corners with two equivalent KO6 octahedra, corners with two equivalent MgO6 octahedra, edges with ten MgO6 octahedra, and edges with two equivalent MgO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 0–5°. There are a spread of K–O bond distances ranging from 2.24–2.73 Å. There are ten 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 KO6 octahedra, corners with two equivalent MgO6 octahedra, corners with two equivalent MgO5 square pyramids, edges with ten MgO6 octahedra, and edges with two equivalent MgO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Mg–O bond distances ranging from 2.00–2.24 Å. In the second Mg site, Mg is bonded to five O atoms to form MgO5 square pyramids that share corners with two equivalent MgO6 octahedra, corners with two equivalent MgO5 square pyramids, corners with two equivalent MgO5 trigonal bipyramids, and edges with eight MgO6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are a spread of Mg–O bond distances ranging from 1.98–2.24 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 KO6 octahedra, edges with five MgO6 octahedra, and edges with two equivalent MgO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 1–30°. There are a spread of Mg–O bond distances ranging from 1.97–2.32 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 seven MgO6 octahedra, edges with two equivalent MgO5 square pyramids, and edges with two equivalent MgO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 2–4°. There are a spread of Mg–O bond distances ranging from 2.04–2.29 Å. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four MgO6 octahedra, edges with two equivalent KO6 octahedra, edges with six MgO6 octahedra, and edges with four equivalent MgO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 0–9°. There are a spread of Mg–O bond distances ranging from 2.05–2.24 Å. In the sixth Mg site, Mg is bonded in a square co-planar geometry to four O atoms. There are a spread of Mg–O bond distances ranging from 2.05–2.15 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent KO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. There are a spread of Mg–O bond distances ranging from 2.06–2.29 Å. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four MgO6 octahedra, edges with eight MgO6 octahedra, and edges with two equivalent MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 0–17°. There are a spread of Mg–O bond distances ranging from 2.05–2.45 Å. In the ninth Mg site, Mg is bonded to five O atoms to form distorted MgO5 trigonal bipyramids that share corners with two equivalent MgO6 octahedra, a cornercorner with one MgO5 square pyramid, corners with three equivalent MgO5 trigonal bipyramids, an edgeedge with one KO6 octahedra, and edges with seven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–31°. There are a spread of Mg–O bond distances ranging from 2.05–2.24 Å. In the tenth Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with four equivalent MgO6 octahedra, corners with two equivalent MgO5 trigonal bipyramids, an edgeedge with one KO6 octahedra, edges with nine MgO6 octahedra, and an edgeedge with one MgO5 square pyramid. The corner-sharing octahedra tilt angles range from 5–9°. There are a spread of Mg–O bond distances ranging from 1.99–2.56 Å. B is bonded in a bent 150 degrees geometry to two equivalent O atoms. Both B–O bond lengths are 1.45 Å. There are eleven inequivalent O sites. In the first O site, O is bonded to one K and five Mg atoms to form OKMg5 octahedra that share corners with four OKMg5 octahedra and edges with ten OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–9°. In the second O site, O is bonded to one K and five Mg atoms to form OKMg5 octahedra that share corners with four OKMg5 octahedra, corners with two equivalent OMg5 square pyramids, and edges with ten OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. In the third O site, O is bonded to five Mg atoms to form OMg5 square pyramids that share corners with two equivalent OKMg5 octahedra, corners with two equivalent OMg5 square pyramids, and edges with eight OMg6 octahedra. The corner-sharing octahedral tilt angles are 6°. In the fourth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg6 octahedra and edges with seven OKMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the fifth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg6 octahedra, edges with seven OKMg5 octahedra, and edges with two equivalent OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 0–9°. In the sixth O site, O is bonded to two equivalent K and four Mg atoms to form OK2Mg4 octahedra that share corners with four OMg6 octahedra and edges with eight OKMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the seventh O site, O is bonded in a square co-planar geometry to four Mg atoms. In the eighth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg6 octahedra and edges with twelve OKMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the ninth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with four OMg6 octahedra, edges with eight OMg6 octahedra, and edges with two equivalent OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 1–7°. In the tenth O site, O is bonded in a 1-coordinate geometry to one K, four Mg, and one B atom. In the eleventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with four equivalent OMg6 octahedra, edges with ten OKMg5 octahedra, and an edgeedge with one OMg5 square pyramid. The corner-sharing octahedra tilt angles range from 2–6°.

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2020-05-03. Materials Data on KMg14BO15 by Materials Project. https://doi.org/10.17188/1724040

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