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DOE OSTI · 1687120

Materials Data on CsRbMg14O15 by Materials Project

Abstract

CsRbMg14O15 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. Cs1+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Cs–O bond distances ranging from 2.69–2.99 Å. Rb1+ is bonded in a 4-coordinate geometry to four O2- atoms. There are two shorter (2.47 Å) and two longer (2.56 Å) Rb–O bond lengths. There are ten inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, edges with six MgO6 octahedra, and edges with four MgO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 5°. There are a spread of Mg–O bond distances ranging from 2.03–2.09 Å. In the second Mg2+ site, Mg2+ is bonded to five O2- atoms to form a mixture of edge and corner-sharing MgO5 trigonal bipyramids. There are one shorter (2.10 Å) and four longer (2.12 Å) Mg–O bond lengths. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four equivalent MgO6 octahedra, a cornercorner with one MgO5 square pyramid, edges with three MgO6 octahedra, and edges with four MgO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 12–21°. There are a spread of Mg–O bond distances ranging from 2.05–2.50 Å. In the fourth Mg2+ site, Mg2+ is bonded to five O2- atoms to form distorted MgO5 square pyramids that share a cornercorner with one MgO6 octahedra, corners with four equivalent MgO5 square pyramids, an edgeedge with one MgO6 octahedra, and edges with two equivalent MgO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 15°. There are a spread of Mg–O bond distances ranging from 2.07–2.34 Å. In the fifth Mg2+ site, Mg2+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.96 Å) and two longer (2.02 Å) Mg–O bond length. In the sixth Mg2+ site, Mg2+ is bonded to six O2- 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, and edges with two equivalent MgO5 square pyramids. The corner-sharing octahedral tilt angles are 5°. There are a spread of Mg–O bond distances ranging from 2.03–2.46 Å. In the seventh Mg2+ site, Mg2+ is bonded to five O2- atoms to form MgO5 trigonal bipyramids that share corners with six 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 2.02–2.23 Å. In the eighth Mg2+ site, Mg2+ is bonded to five O2- atoms to form MgO5 trigonal bipyramids that share a cornercorner with one MgO6 octahedra, corners with four MgO5 trigonal bipyramids, edges with four MgO6 octahedra, and edges with four equivalent MgO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 2.08–2.10 Å. In the ninth Mg2+ site, Mg2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Mg–O bond distances ranging from 1.93–2.44 Å. In the tenth Mg2+ site, Mg2+ is bonded to five O2- atoms to form distorted MgO5 trigonal bipyramids that share corners with five MgO5 trigonal bipyramids, edges with three MgO6 octahedra, and edges with four MgO5 trigonal bipyramids. There are a spread of Mg–O bond distances ranging from 2.10–2.29 Å. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded to five Mg2+ atoms to form OMg5 square pyramids that share a cornercorner with one OCsMg5 octahedra, corners with two equivalent OMg5 square pyramids, corners with two equivalent OCs2Mg3 trigonal bipyramids, and edges with four ORbMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the second O2- site, O2- is bonded to five Mg2+ atoms to form distorted OMg5 trigonal bipyramids that share corners with four OCsMg5 octahedra, corners with four OMg5 trigonal bipyramids, and edges with four equivalent OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 23–61°. In the third O2- site, O2- is bonded to one Cs1+ and five Mg2+ atoms to form OCsMg5 octahedra that share corners with two equivalent OCsMg5 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 square pyramids. The corner-sharing octahedral tilt angles are 4°. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to six Mg2+ atoms. In the fifth O2- site, O2- is bonded to five Mg2+ atoms to form OMg5 square pyramids that share corners with four equivalent OMg5 square pyramids, edges with five OCsMg5 octahedra, and edges with three OMg5 trigonal bipyramids. In the sixth O2- site, O2- is bonded to two equivalent Rb1+ and three Mg2+ atoms to form distorted ORb2Mg3 trigonal bipyramids that share corners with two equivalent OMg6 octahedra, corners with four OMg5 trigonal bipyramids, edges with four equivalent ORbMg5 octahedra, and edges with two equivalent OMg5 square pyramids. The corner-sharing octahedral tilt angles are 4°. In the seventh O2- site, O2- is bonded to six Mg2+ atoms to form OMg6 octahedra that share corners with two equivalent OMg6 octahedra, corners with three OCs2Mg3 trigonal bipyramids, edges with six OCsMg5 octahedra, and edges with four OMg5 square pyramids. The corner-sharing octahedral tilt angles are 5°. In the eighth O2- site, O2- is bonded in a 5-coordinate geometry to five Mg2+ atoms. In the ninth O2- site, O2- is bonded to two equivalent Cs1+ and three Mg2+ atoms to form distorted OCs2Mg3 trigonal bipyramids that share corners with three OCsMg5 octahedra, corners with two equivalent OMg5 square pyramids, and corners with two equivalent OCs2Mg3 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 0–51°. In the tenth O2- site, O2- is bonded to one Rb1+ and five Mg2+ atoms to form distorted ORbMg5 octahedra that share corners with four equivalent ORbMg5 octahedra, a cornercorner with one OMg5 trigonal bipyramid, edges with three OCsMg5 octahedra, edges with three OMg5 square pyramids, and edges with two equivalent ORb2Mg3 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 2–48°. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to one Cs1+ and four Mg2+ atoms.

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2020-05-02. Materials Data on CsRbMg14O15 by Materials Project. https://doi.org/10.17188/1687120

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