DOI: 10.17188/1689663
title: Materials Data on Mg30CrBiO32 by Materials Project

description: Mg30CrBiO32 is alpha Po-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are eight 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 CrO6 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 2.04–2.18 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent BiO6 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 1.99–2.18 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.14 Å) and two longer (2.17 Å) Mg–O bond lengths. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.14 Å) and two longer (2.16 Å) Mg–O bond lengths. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one CrO6 octahedra, an edgeedge with one BiO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 3–5°. There are a spread of Mg–O bond distances ranging from 2.10–2.23 Å. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Mg–O bond distances ranging from 2.15–2.17 Å. In the seventh Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one CrO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–6°. There are two shorter (2.15 Å) and four longer (2.17 Å) Mg–O bond lengths. In the eighth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, an edgeedge with one BiO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 2–6°. There are a spread of Mg–O bond distances ranging from 2.10–2.22 Å. Cr3+ is bonded to six O2- atoms to form CrO6 octahedra that share corners with two equivalent BiO6 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 (2.01 Å) and four longer (2.28 Å) Cr–O bond lengths. Bi1+ is bonded to six O2- atoms to form BiO6 octahedra that share corners with two equivalent CrO6 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 (2.32 Å) and four longer (2.33 Å) Bi–O bond lengths. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded to five Mg2+ and one Cr3+ atom to form a mixture of corner and edge-sharing OMg5Cr octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the second O2- site, O2- is bonded to five Mg2+ and one Bi1+ atom to form OMg5Bi octahedra that share corners with six OMg5Cr octahedra and edges with twelve OMg5Bi octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the third O2- site, O2- is bonded to six Mg2+ atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the fourth O2- site, O2- is bonded to six Mg2+ atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–2°. In the fifth O2- site, O2- is bonded to five Mg2+ and one Bi1+ atom to form OMg5Bi octahedra that share corners with six OMg5Cr octahedra and edges with twelve OMg5Bi octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are two shorter (2.22 Å) and two longer (2.23 Å) O–Mg bond lengths. In the sixth O2- site, O2- is bonded to six Mg2+ atoms to form OMg6 octahedra that share corners with six OMg6 octahedra and edges with twelve OMg5Bi octahedra. The corner-sharing octahedra tilt angles range from 0–2°. There are two shorter (2.10 Å) and two longer (2.17 Å) O–Mg bond lengths. In the seventh O2- site, O2- is bonded to six Mg2+ atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra and edges with twelve OMg5Cr octahedra. The corner-sharing octahedra tilt angles range from 1–5°. In the eighth O2- site, O2- is bonded to four equivalent Mg2+, one Cr3+, and one Bi1+ atom to form OMg4CrBi octahedra that share corners with six OMg4CrBi octahedra and edges with twelve OMg5Cr octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the ninth O2- site, O2- is bonded to six Mg2+ atoms to form OMg6 octahedra that share corners with six OMg4CrBi octahedra and edges with twelve OMg5Cr octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the tenth O2- site, O2- is bonded to six Mg2+ atoms to form OMg6 octahedra that share corners with six OMg4CrBi octahedra and edges with twelve OMg5Cr octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are two shorter (2.10 Å) and two longer (2.16 Å) O–Mg bond lengths. In the eleventh O2- site, O2- is bonded to six Mg2+ atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedral tilt angles are 0°.