DOI: 10.17188/1685228
title: Materials Data on RbMg14BO15 by Materials Project

description: RbMg14BO15 crystallizes in the orthorhombic Pmm2 space group. The structure is three-dimensional. Rb is bonded in a 2-coordinate geometry to five O atoms. There are a spread of Rb–O bond distances ranging from 2.33–2.80 Å. There are ten inequivalent Mg sites. In the first 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, and edges with eight MgO6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are a spread of Mg–O bond distances ranging from 2.03–2.26 Å. In the second 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, and edges with ten MgO6 octahedra. The corner-sharing octahedral tilt angles are 5°. There are a spread of Mg–O bond distances ranging from 2.00–2.31 Å. In the third Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–31°. There are a spread of Mg–O bond distances ranging from 1.99–2.35 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, and edges with two equivalent MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 1–3°. There are a spread of Mg–O bond distances ranging from 2.04–2.39 Å. In the fifth Mg site, Mg is bonded in a distorted T-shaped geometry to three O atoms. There are one shorter (2.06 Å) and two longer (2.09 Å) Mg–O bond lengths. In the sixth Mg site, Mg is bonded to six O atoms to form a mixture of distorted edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–23°. There are a spread of Mg–O bond distances ranging from 2.07–2.56 Å. In the seventh 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 1–7°. There are a spread of Mg–O bond distances ranging from 1.99–2.27 Å. In the eighth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. There are a spread of Mg–O bond distances ranging from 2.05–2.26 Å. In the ninth Mg site, Mg is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Mg–O bond distances ranging from 1.94–2.64 Å. In the tenth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four equivalent MgO6 octahedra, edges with nine MgO6 octahedra, and an edgeedge with one MgO5 square pyramid. The corner-sharing octahedra tilt angles range from 4–9°. There are a spread of Mg–O bond distances ranging from 2.01–2.26 Å. B is bonded in a distorted trigonal planar geometry to three O atoms. There is two shorter (1.44 Å) and one longer (1.50 Å) B–O bond length. There are eleven inequivalent O sites. In the first O site, O is bonded to five Mg atoms to form OMg5 trigonal bipyramids that share a cornercorner with one OMg5B octahedra, corners with two equivalent OMg5 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 distorted ORbMg5 octahedra that share corners with four ORbMg5 octahedra and edges with eight OMg6 octahedra. The corner-sharing octahedra tilt angles range from 1–7°. In the third O site, O is bonded to five Mg and one B atom to form distorted OMg5B octahedra that share corners with four ORbMg5 octahedra, a cornercorner with one OMg5 trigonal bipyramid, and edges with eight OMg6 octahedra. The corner-sharing octahedra tilt angles range from 1–5°. In the fourth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg6 octahedra, edges with four OMg6 octahedra, and edges with two equivalent OMg5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 1–16°. In the fifth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg6 octahedra and edges with eight ORbMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the sixth O site, O is bonded in a 5-coordinate geometry to two equivalent Rb and three Mg atoms. 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 four OMg6 octahedra and edges with ten ORbMg5 octahedra. The corner-sharing octahedra tilt angles range from 1–2°. 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 ten OMg5B octahedra, and edges with two equivalent OMg5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 1–5°. In the tenth O site, O is bonded in a distorted single-bond geometry to one Rb, 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 ORbMg5 octahedra, and an edgeedge with one OMg5 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 1–4°.