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DOE OSTI · 1694984

Materials Data on RbMg14BO15 by Materials Project

Abstract

RbMg14BO15 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. Rb is bonded in a 3-coordinate geometry to five O atoms. There are a spread of Rb–O bond distances ranging from 2.38–2.82 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 MgO6 octahedra, corners with two equivalent MgO5 square pyramids, edges with two equivalent MgO6 octahedra, edges with four equivalent MgO5 square pyramids, and edges with six MgO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 3°. There are a spread of Mg–O bond distances ranging from 2.02–2.16 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 four MgO5 trigonal bipyramids, edges with four equivalent MgO5 square pyramids, and edges with two equivalent MgO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 4°. There are a spread of Mg–O bond distances ranging from 2.00–2.18 Å. In the third Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with four equivalent MgO6 octahedra, a cornercorner with one MgO5 square pyramid, corners with three MgO5 trigonal bipyramids, an edgeedge with one MgO6 octahedra, and edges with three MgO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 4–32°. There are a spread of Mg–O bond distances ranging from 1.99–2.53 Å. In the fourth Mg site, Mg is bonded to five O atoms to form MgO5 square pyramids that share a cornercorner with one MgO6 octahedra, corners with four equivalent MgO5 square pyramids, corners with three MgO5 trigonal bipyramids, edges with three MgO6 octahedra, edges with two equivalent MgO5 square pyramids, and edges with two equivalent MgO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 1°. There are a spread of Mg–O bond distances ranging from 1.99–2.16 Å. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, a cornercorner with one MgO5 trigonal bipyramid, edges with four MgO6 octahedra, edges with two equivalent MgO5 square pyramids, and edges with four equivalent MgO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 10°. There are a spread of Mg–O bond distances ranging from 1.94–2.27 Å. In the sixth Mg site, Mg is bonded in a distorted square co-planar geometry to four O atoms. There are a spread of Mg–O bond distances ranging from 2.01–2.21 Å. In the seventh Mg site, Mg is bonded to five O atoms to form MgO5 trigonal bipyramids that share corners with three MgO6 octahedra, corners with two equivalent MgO5 square pyramids, corners with four MgO5 trigonal bipyramids, edges with two equivalent MgO6 octahedra, and edges with four equivalent MgO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 0–70°. There are a spread of Mg–O bond distances ranging from 2.07–2.16 Å. In the eighth Mg site, Mg is bonded to five O atoms to form MgO5 trigonal bipyramids that share corners with two equivalent MgO5 square pyramids, corners with four MgO5 trigonal bipyramids, edges with two equivalent MgO6 octahedra, and edges with four equivalent MgO5 trigonal bipyramids. There are a spread of Mg–O bond distances ranging from 2.12–2.28 Å. In the ninth Mg site, Mg is bonded to five O atoms to form distorted MgO5 trigonal bipyramids that share a cornercorner with one MgO5 square pyramid, corners with four MgO5 trigonal bipyramids, edges with five MgO6 octahedra, and edges with two equivalent MgO5 square pyramids. There are a spread of Mg–O bond distances ranging from 2.03–2.28 Å. In the tenth Mg site, Mg is bonded to five O atoms to form MgO5 trigonal bipyramids that share corners with two equivalent MgO6 octahedra, corners with two equivalent MgO5 square pyramids, corners with five MgO5 trigonal bipyramids, an edgeedge with one MgO6 octahedra, an edgeedge with one MgO5 square pyramid, and edges with four MgO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 77°. There are a spread of Mg–O bond distances ranging from 2.00–2.22 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 five Mg atoms to form distorted OMg5 square pyramids that share a cornercorner with one ORbMg5 octahedra, corners with two equivalent OMg5 square pyramids, corners with two equivalent ORb2Mg3 trigonal bipyramids, and edges with eight OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second O site, O is bonded to one Rb and five Mg atoms to form ORbMg5 octahedra that share corners with two equivalent ORbMg5 octahedra, a cornercorner with one OMg5 square pyramid, corners with four OMg5 trigonal bipyramids, edges with four OMg6 octahedra, and edges with four equivalent OMg5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 6°. In the third O site, O is bonded to five Mg atoms to form OMg5 trigonal bipyramids that share corners with two equivalent ORbMg5 octahedra, corners with two equivalent OMg5 square pyramids, corners with two equivalent OMg5 trigonal bipyramids, edges with two equivalent OMg6 octahedra, and edges with four equivalent OMg5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 4°. In the fourth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with four equivalent OMg6 octahedra, a cornercorner with one OMg5 trigonal bipyramid, edges with three OMg6 octahedra, edges with three OMg5 square pyramids, and an edgeedge with one ORb2Mg3 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 1–5°. In the fifth O site, O is bonded to five Mg atoms to form distorted OMg5 trigonal bipyramids that share corners with four OMg6 octahedra, corners with five OMg5 trigonal bipyramids, edges with two equivalent ORbMg5 octahedra, and edges with two equivalent OMg5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 3–76°. In the sixth O site, O is bonded to two equivalent Rb and three Mg atoms to form ORb2Mg3 trigonal bipyramids that share corners with three ORbMg5 octahedra, corners with two equivalent OMg5 square pyramids, corners with four OMg5 trigonal bipyramids, and edges with two equivalent OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–65°. In the seventh O site, O is bonded in a distorted 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 two equivalent OMg6 octahedra, corners with two equivalent OMg5 square pyramids, corners with three OMg5 trigonal bipyramids, edges with eight ORbMg5 octahedra, and edges with two equivalent OMg5 square pyramids. The corner-sharing octahedral tilt angles are 3°. In the ninth O site, O is bonded to five Mg atoms to form OMg5 square pyramids that share corners with two equivalent OMg6 octahedra, corners with two equivalent OMg5 square pyramids, corners with two equivalent OMg5 trigonal bipyramids, and edges with six OMg6 octahedra. The corner-sharing octahedral tilt angles are 5°. In the tenth O site, O is bonded in a 1-coordinate geometry to one Rb, three 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, corners with two equivalent OMg5 trigonal bipyramids, edges with five ORbMg5 octahedra, edges with three OMg5 square pyramids, and an edgeedge with one OMg5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 3–11°.

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2020-04-29. Materials Data on RbMg14BO15 by Materials Project. https://doi.org/10.17188/1694984

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