DOI: 10.17188/1745804
title: Materials Data on Mg30AlCdO32 by Materials Project

description: Mg30CdAlO32 is Molybdenum Carbide MAX Phase-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are eight 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 AlO6 octahedra, corners with four MgO6 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 2.10–2.23 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent CdO6 octahedra, corners with four MgO6 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 1.99–2.19 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 octahedral tilt angles are 0°. There are two shorter (2.13 Å) and four longer (2.16 Å) Mg–O bond lengths. In the fourth Mg site, Mg is bonded to six O atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.12 Å) and two longer (2.15 Å) Mg–O bond lengths. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one CdO6 octahedra, an edgeedge with one AlO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–15°. There are a spread of Mg–O bond distances ranging from 2.12–2.19 Å. In the sixth 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 1–3°. There are two shorter (2.14 Å) and four longer (2.15 Å) Mg–O bond lengths. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one AlO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–5°. There are four shorter (2.14 Å) and two longer (2.15 Å) Mg–O bond lengths. In the eighth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one CdO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–7°. There are a spread of Mg–O bond distances ranging from 2.13–2.17 Å. Cd is bonded to six O atoms to form CdO6 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 (2.30 Å) and two longer (2.43 Å) Cd–O bond lengths. Al is bonded to six O atoms to form AlO6 octahedra that share corners with two equivalent CdO6 octahedra, corners with four equivalent MgO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There is two shorter (1.86 Å) and four longer (2.06 Å) Al–O bond length. There are fourteen inequivalent O sites. In the first O site, O is bonded to five Mg and one Al atom to form OMg5Al octahedra that share corners with six OMg5Al octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are two shorter (2.14 Å) and one longer (2.23 Å) O–Mg bond lengths. In the second O site, O is bonded to five Mg and one Cd atom to form OMg5Cd octahedra that share corners with six OMg5Al octahedra and edges with twelve OMg5Cd octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the third O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg5Al octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. Both O–Mg bond lengths are 2.15 Å. In the fourth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the fifth O site, O is bonded to five Mg and one Cd atom to form OMg5Cd octahedra that share corners with six OMg5Al octahedra and edges with twelve OMg5Cd octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are two shorter (2.15 Å) and two longer (2.17 Å) O–Mg bond lengths. In the sixth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg5Al octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are two shorter (2.14 Å) and two longer (2.15 Å) O–Mg bond lengths. In the seventh 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 1–2°. In the eighth O site, O is bonded to four equivalent Mg, one Cd, and one Al atom to form distorted OMg4AlCd octahedra that share corners with six OMg4AlCd octahedra and edges with twelve OMg5Al octahedra. The corner-sharing octahedra tilt angles range from 0–9°. In the ninth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg4AlCd octahedra and edges with twelve OMg5Cd octahedra. The corner-sharing octahedra tilt angles range from 0–9°. In the tenth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg4AlCd octahedra and edges with twelve OMg5Cd octahedra. The corner-sharing octahedra tilt angles range from 0–9°. There are two shorter (2.12 Å) and two longer (2.15 Å) O–Mg bond lengths. In the eleventh O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the twelfth 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 0–3°. In the thirteenth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. The O–Mg bond length is 2.13 Å. In the fourteenth O site, O is bonded to six Mg atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of O–Mg bond distances ranging from 2.13–2.15 Å.