Materials Data on CaMg14SiO16 by Materials Project

Abstract

CaMg14SiO16 is alpha Po-derived structured and crystallizes in the orthorhombic Pmmm space group. The structure is three-dimensional. Ca is bonded to six O atoms to form CaO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with two equivalent MgO6 octahedra, corners with two equivalent SiO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Ca–O bond distances ranging from 2.18–2.29 Å. 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 CaO6 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 2.05–2.18 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent SiO6 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 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 CaO6 octahedra, edges with two equivalent SiO6 octahedra, and edges with eight MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Mg–O bond distances ranging from 2.13–2.19 Å. 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 octahedra tilt angles range from 0–1°. There are a spread of Mg–O bond distances ranging from 2.15–2.18 Å. In the fifth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent CaO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. There are a spread of Mg–O bond distances ranging from 2.12–2.22 Å. In the sixth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent SiO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. There are a spread of Mg–O bond distances ranging from 2.14–2.20 Å. In the seventh Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with six MgO6 octahedra, edges with two equivalent SiO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. There are a spread of Mg–O bond distances ranging from 2.14–2.20 Å. In the eighth 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 CaO6 octahedra, an edgeedge with one SiO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–4°. There are a spread of Mg–O bond distances ranging from 2.12–2.21 Å. Si is bonded to six O atoms to form SiO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with two equivalent MgO6 octahedra, corners with two equivalent SiO6 octahedra, and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Si–O bond distances ranging from 2.10–2.30 Å. There are eleven inequivalent O sites. In the first O site, O is bonded to one Ca and five Mg atoms to form OCaMg5 octahedra that share corners with six OCaMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the second O site, O is bonded to five Mg and one Si atom to form OMg5Si octahedra that share corners with six OCaMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the third O site, O is bonded to one Ca and five Mg atoms to form OCaMg5 octahedra that share corners with six OCaMg5 octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. All O–Mg bond lengths are 2.18 Å. In the fourth O site, O is bonded to five Mg and one Si atom to form OMg5Si octahedra that share corners with six OMg5Si octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. Both O–Mg bond lengths are 2.14 Å. In the fifth 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 OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the sixth O site, O is bonded to two equivalent Ca and four Mg atoms to form OCa2Mg4 octahedra that share corners with six OCa2Mg4 octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the seventh O site, O is bonded to four Mg and two equivalent Si atoms to form OMg4Si2 octahedra that share corners with six OCa2Mg4 octahedra and edges with twelve OMg5Si octahedra. The corner-sharing octahedral tilt angles are 0°. In the eighth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OCa2Mg4 octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedral tilt angles are 0°. In the ninth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg4Si2 octahedra and edges with twelve OMg5Si octahedra. The corner-sharing octahedral tilt angles are 0°. In the tenth O site, O is bonded to one Ca, four Mg, and one Si atom to form OCaMg4Si octahedra that share corners with six OCaMg4Si octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the eleventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OCaMg4Si octahedra and edges with twelve OCaMg5 octahedra. The corner-sharing octahedral tilt angles are 0°.