DOI: 10.17188/1711028
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 5-coordinate geometry to five O atoms. There are a spread of Rb–O bond distances ranging from 2.47–2.80 Å. There are ten inequivalent Mg sites. In the first Mg site, Mg is bonded in a distorted see-saw-like geometry to four O atoms. There are two shorter (1.95 Å) and two longer (2.16 Å) Mg–O bond lengths. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, edges with six MgO6 octahedra, and edges with six MgO5 square pyramids. The corner-sharing octahedral tilt angles are 1°. There are a spread of Mg–O bond distances ranging from 2.00–2.11 Å. In the third Mg site, Mg is bonded to five O atoms to form distorted MgO5 square pyramids that share corners with two MgO6 octahedra, corners with four equivalent MgO5 square pyramids, an edgeedge with one MgO6 octahedra, and edges with two equivalent MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 8–58°. There are a spread of Mg–O bond distances ranging from 2.11–2.50 Å. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four equivalent MgO6 octahedra, a cornercorner with one MgO5 square pyramid, edges with four MgO6 octahedra, and edges with five MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 4–11°. There are a spread of Mg–O bond distances ranging from 2.08–2.21 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 square pyramid, edges with four MgO6 octahedra, and edges with six MgO5 square pyramids. The corner-sharing octahedral tilt angles are 9°. There are a spread of Mg–O bond distances ranging from 1.97–2.28 Å. In the sixth Mg site, Mg is bonded in a distorted T-shaped geometry to three O atoms. There is one shorter (1.96 Å) and two longer (2.00 Å) Mg–O bond length. In the seventh Mg site, Mg is bonded to five O atoms to form MgO5 square pyramids that share corners with three MgO6 octahedra, corners with two equivalent MgO5 square pyramids, edges with four MgO6 octahedra, and edges with four equivalent MgO5 square pyramids. The corner-sharing octahedra tilt angles range from 0–2°. There are a spread of Mg–O bond distances ranging from 2.05–2.09 Å. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent MgO6 octahedra, corners with four MgO5 square pyramids, edges with two equivalent MgO6 octahedra, and edges with four equivalent MgO5 square pyramids. The corner-sharing octahedral tilt angles are 39°. There are a spread of Mg–O bond distances ranging from 2.16–2.21 Å. In the ninth Mg site, Mg is bonded to five O atoms to form MgO5 square pyramids that share corners with four MgO5 square pyramids, edges with five MgO6 octahedra, and edges with two equivalent MgO5 square pyramids. There are a spread of Mg–O bond distances ranging from 2.05–2.20 Å. In the tenth Mg site, Mg is bonded to five O atoms to form MgO5 square pyramids that share corners with five MgO5 square pyramids, edges with five MgO6 octahedra, and edges with two equivalent MgO5 square pyramids. There are a spread of Mg–O bond distances ranging from 2.01–2.20 Å. B is bonded in a distorted single-bond geometry to five O atoms. There are a spread of B–O bond distances ranging from 1.47–2.18 Å. There are eleven inequivalent O sites. In the first O site, O is bonded to five Mg atoms to form 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 OMg4B trigonal bipyramids, edges with four OMg6 octahedra, and edges with four equivalent OMg5 square pyramids. The corner-sharing octahedral tilt angles are 2°. In the third O site, O is bonded to four Mg and one B atom to form distorted OMg4B trigonal bipyramids that share corners with two equivalent ORbMg5 octahedra, corners with two equivalent OMg4B trigonal bipyramids, edges with four OMg4B2 octahedra, and edges with four equivalent OMg5 square pyramids. The corner-sharing octahedral tilt angles are 8°. 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 square pyramid, edges with four OMg6 octahedra, edges with two equivalent OMg5 square pyramids, and an edgeedge with one ORb2Mg3 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 4–25°. In the fifth O site, O is bonded to five Mg atoms to form OMg5 square pyramids that share a cornercorner with one OMg6 octahedra, corners with four equivalent OMg5 square pyramids, edges with six ORbMg5 octahedra, and edges with two equivalent OMg4B trigonal bipyramids. The corner-sharing octahedral tilt angles are 2°. 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 two equivalent ORb2Mg3 trigonal bipyramids, and edges with two equivalent OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–57°. In the seventh O site, O is bonded in a 5-coordinate geometry to five 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, a cornercorner with one ORb2Mg3 trigonal bipyramid, edges with eight ORbMg5 octahedra, and edges with four OMg5 square pyramids. The corner-sharing octahedra tilt angles range from 1–4°. In the ninth O site, O is bonded to four Mg and two equivalent B atoms to form OMg4B2 octahedra that share corners with four OMg6 octahedra, edges with six OMg6 octahedra, edges with two equivalent OMg5 square pyramids, and edges with two equivalent OMg4B trigonal bipyramids. The corner-sharing octahedra tilt angles range from 1–4°. In the tenth O site, O is bonded in a 5-coordinate geometry to one Rb and four Mg atoms. In the eleventh O site, O is bonded to five Mg and one B atom to form OMg5B octahedra that share corners with four equivalent OMg5B octahedra, edges with seven ORbMg5 octahedra, edges with three OMg5 square pyramids, and an edgeedge with one OMg4B trigonal bipyramid. The corner-sharing octahedra tilt angles range from 3–11°.