DOI: 10.17188/1747169
title: Materials Data on BaMg14AlO16 by Materials Project

description: BaMg14AlO16 is Caswellsilverite-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ba is bonded to six O atoms to form BaO6 octahedra that share corners with two equivalent BaO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.27 Å) and four longer (2.47 Å) Ba–O bond lengths. There are five 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 BaO6 octahedra, corners with two equivalent MgO6 octahedra, corners with two equivalent AlO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Mg–O bond distances ranging from 1.90–2.42 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent AlO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–11°. There are a spread of Mg–O bond distances ranging from 2.17–2.28 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 BaO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–8°. There are a spread of Mg–O bond distances ranging from 2.07–2.31 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 two equivalent BaO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–8°. There are a spread of Mg–O bond distances ranging from 2.07–2.31 Å. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six equivalent MgO6 octahedra, an edgeedge with one BaO6 octahedra, an edgeedge with one AlO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 4–11°. There are two shorter (2.13 Å) and four longer (2.27 Å) Mg–O bond lengths. Al is bonded to six O atoms to form AlO6 octahedra that share corners with two equivalent AlO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.95 Å) and two longer (2.27 Å) Al–O bond lengths. There are nine inequivalent O sites. In the first O site, O is bonded to five Mg and one Al atom to form a mixture of edge and corner-sharing OMg5Al octahedra. The corner-sharing octahedra tilt angles range from 0–11°. In the second O site, O is bonded to one Ba and five Mg atoms to form a mixture of edge and corner-sharing OBaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. Both O–Mg bond lengths are 2.28 Å. In the third O site, O is bonded to one Ba and five Mg atoms to form a mixture of edge and corner-sharing OBaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. There are two shorter (2.27 Å) and two longer (2.28 Å) O–Mg bond lengths. In the fourth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OMg5Al octahedra. The corner-sharing octahedra tilt angles range from 1–6°. In the fifth O site, O is bonded to four equivalent Mg and two equivalent Al atoms to form OMg4Al2 octahedra that share corners with six OMg4Al2 octahedra and edges with twelve OMg5Al octahedra. The corner-sharing octahedral tilt angles are 0°. In the sixth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg4Al2 octahedra and edges with twelve OMg5Al octahedra. The corner-sharing octahedral tilt angles are 0°. In the seventh O site, O is bonded to two equivalent Ba and four Mg atoms to form OBa2Mg4 octahedra that share corners with six OMg6 octahedra and edges with twelve OBaMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the eighth O site, O is bonded to one Ba and five Mg atoms to form a mixture of edge and corner-sharing OBaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. The O–Mg bond length is 1.90 Å. In the ninth O site, O is bonded to one Ba and five Mg atoms to form a mixture of edge and corner-sharing OBaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. There are one shorter (1.90 Å) and two longer (2.27 Å) O–Mg bond lengths.