Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Al-Mg-O-Si”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

17 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Mg3Al2(SiO4)3 by Materials Project

Mg3Al2Si3O12 crystallizes in the cubic Ia-3d space group. The structure is three-dimensional. Mg2+ is bonded in a distorted body-centered cubic geometry to eight equivalent O2- atoms. There are four shorter (2.22 Å) and four longer (2.37 Å) Mg–O bond lengths. Al3+ is bonded to six equivalent O2- atoms to form AlO6 octahedra that share corners with six equivalent SiO4 tetrahedra. All Al–O bond lengths are 1.90 Å. Si4+ is bonded to four equivalent O2- atoms to form SiO4 tetrahedra that share corners with four equivalent AlO6 octahedra. The corner-sharing octahedral tilt angles are 49°. All Si–O bond lengths are 1.65 Å. O2- is bonded in a 4-coordinate geometry to two equivalent Mg2+, one Al3+, and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2Al4Si5O18 by Materials Project

Mg2Al4Si5O18 crystallizes in the orthorhombic Cccm space group. The structure is three-dimensional. Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent AlO4 tetrahedra, corners with four SiO4 tetrahedra, an edgeedge with one SiO4 tetrahedra, and edges with two equivalent AlO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.12–2.14 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form distorted AlO4 tetrahedra that share corners with four SiO4 tetrahedra and edges with two equivalent MgO6 octahedra. All Al–O bond lengths are 1.77 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two equivalent MgO6 octahedra and corners with four SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 48°. There are a spread of Al–O bond distances ranging from 1.72–1.79 Å. There are three inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent MgO6 octahedra, a cornercorner with one SiO4 tetrahedra, and corners with three AlO4 tetrahedra. The corner-sharing octahedral tilt angles are 42°. There are a spread of Si–O bond distances ranging from 1.60–1.66 Å. In the second Si4+ site, Si4+ is bonded to four equivalent O2- atoms to form SiO4 tetrahedra that share corners with four equivalent AlO4 tetrahedra and edges with two equivalent MgO6 octahedra. All Si–O bond lengths are 1.65 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two equivalent MgO6 octahedra, a cornercorner with one SiO4 tetrahedra, and corners with three AlO4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are a spread of Si–O bond distances ranging from 1.59–1.66 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a linear geometry to two Si4+ atoms. In the fourth O2- site, O2- is bonded in a linear geometry to one Al3+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a linear geometry to one Al3+ and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2Al4Si5O18 by Materials Project

Mg2Al4Si5O18 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra, an edgeedge with one SiO4 tetrahedra, and edges with two AlO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.24 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with three AlO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.09–2.18 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with three AlO4 tetrahedra, corners with three SiO4 tetrahedra, an edgeedge with one SiO4 tetrahedra, and edges with two AlO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 1.99–2.22 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form distorted MgO6 octahedra that share corners with three AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with three AlO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 2.00–2.28 Å. There are eight inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form distorted AlO4 tetrahedra that share corners with two AlO4 tetrahedra, corners with two SiO4 tetrahedra, and edges with two MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.74–1.82 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra and edges with two MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.76–1.78 Å. In the third Al3+ site, Al3+ is bonded to four O2- atoms to form distorted AlO4 tetrahedra that share corners with four SiO4 tetrahedra and edges with two MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.76–1.78 Å. In the fourth Al3+ site, Al3+ is bonded to four O2- atoms to form distorted AlO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with two MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.73–1.79 Å. In the fifth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with two MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.72–1.79 Å. In the sixth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two MgO6 octahedra, a cornercorner with one AlO4 tetrahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–50°. There are a spread of Al–O bond distances ranging from 1.72–1.80 Å. In the seventh Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two MgO6 octahedra, corners with two AlO4 tetrahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–47°. There are a spread of Al–O bond distances ranging from 1.73–1.76 Å. In the eighth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two MgO6 octahedra, a cornercorner with one AlO4 tetrahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 42–50°. There are a spread of Al–O bond distances ranging from 1.72–1.79 Å. There are ten inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two MgO6 octahedra, a cornercorner with one AlO4 tetrahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–48°. There are a spread of Si–O bond distances ranging from 1.63–1.69 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two MgO6 octahedra, a cornercorner with one SiO4 tetrahedra, and corners with three AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 43–44°. There are a spread of Si–O bond distances ranging from 1.59–1.66 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two MgO6 octahedra, corners with two AlO4 tetrahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–49°. There are a spread of Si–O bond distances ranging from 1.58–1.72 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two MgO6 octahedra, a cornercorner with one SiO4 tetrahedra, and corners with three AlO4 tetrahedra. The corner-sharing octahedral tilt angles are 43°. There are a spread of Si–O bond distances ranging from 1.58–1.66 Å. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two MgO6 octahedra, a cornercorner with one SiO4 tetrahedra, and corners with three AlO4 tetrahedra. The corner-sharing octahedral tilt angles are 41°. There are a spread of Si–O bond distances ranging from 1.59–1.66 Å. In the sixth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two MgO6 octahedra, corners with two AlO4 tetrahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 43–44°. There is one shorter (1.62 Å) and three longer (1.65 Å) Si–O bond length. In the seventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two MgO6 octahedra and corners with four AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 43–44°. There are a spread of Si–O bond distances ranging from 1.59–1.67 Å. In the eighth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two MgO6 octahedra, corners with two AlO4 tetrahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–42°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. In the ninth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two MgO6 octahedra, corners with two AlO4 tetrahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 43–44°. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the tenth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two AlO4 tetrahedra, corners with two SiO4 tetrahedra, and edges with two MgO6 octahedra. There is two shorter (1.62 Å) and two longer (1.69 Å) Si–O bond length. There are thirty-six inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to one Al3+ and one Si4+ atom. In the second O2- site, O2- is bonded in a linear geometry to two Si4+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two Si4+ atoms. In the sixth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+, one Al3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a linear geometry to one Al3+ and one Si4+ atom. In the tenth O2- site, O2- is bonded in a linear geometry to two Si4+ atoms. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+, one Al3+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the fifteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+, one Al3+, and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+, one Al3+, and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a linear geometry to two Si4+ atoms. In the eighteenth O2- site, O2- is bonded in a linear geometry to one Al3+ and one Si4+ atom. In the nineteenth O2- site, O2- is bonded in a linear geometry to two Si4+ atoms. In the twentieth O2- site, O2- is bonded in a linear geometry to two Si4+ atoms. In the twenty-first O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the twenty-second O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the twenty-third O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the twenty-fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the twenty-fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the twenty-sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the twenty-seventh O2- site, O2- is bonded in a linear geometry to one Al3+ and one Si4+ atom. In the twenty-eighth O2- site, O2- is bonded in a linear geometry to two Si4+ atoms. In the twenty-ninth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two Al3+ atoms. In the thirtieth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two Al3+ atoms. In the thirty-first O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the thirty-second O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two Al3+ atoms. In the thirty-third O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+, one Al3+, and one Si4+ atom. In the thirty-fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two Al3+ atoms. In the thirty-fifth O2- site, O2- is bonded in a linear geometry to one Al3+ and one Si4+ atom. In the thirty-sixth O2- site, O2- is bonded in a linear geometry to one Al3+ and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg30AlSiO32 by Materials Project

Mg30AlSiO32 is alpha Po-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 MgO6 octahedra, corners with two equivalent AlO6 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 Mg–O bond distances ranging from 2.03–2.29 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 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 (2.12 Å) and two longer (2.27 Å) Mg–O bond lengths. 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 a spread of Mg–O bond distances ranging from 2.13–2.16 Å. In the fourth Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with two equivalent SiO6 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 (2.06 Å) and four longer (2.16 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 AlO6 octahedra, an edgeedge with one SiO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–8°. There are two shorter (2.13 Å) and four longer (2.15 Å) Mg–O bond lengths. 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 0–1°. 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 1–8°. There are two shorter (2.14 Å) and four 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 SiO6 octahedra, and edges with eleven MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are a spread of Mg–O bond distances ranging from 2.13–2.16 Å. Al is bonded to six O atoms to form AlO6 octahedra that share corners with six MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.00 Å) and two longer (2.01 Å) Al–O bond lengths. Si is bonded to six O atoms to form SiO6 octahedra that share corners with six MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are two shorter (2.23 Å) and four longer (2.26 Å) Si–O bond lengths. There are seventeen 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 0–4°. In the second 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 0–4°. In the third O site, O is bonded to five Mg and one Si atom to form a mixture of edge and corner-sharing OMg5Si octahedra. The corner-sharing octahedra tilt angles range from 0–1°. 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 0–1°. In the fifth 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 0–7°. In the sixth O site, O is bonded to five Mg and one Si atom to form OMg5Si octahedra that share corners with six OMg5Al octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–7°. The O–Mg bond length is 2.03 Å. In the seventh O site, O is bonded to five Mg and one Si atom to form OMg5Si octahedra that share corners with six OMg5Al octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–7°. There are a spread of O–Mg bond distances ranging from 2.03–2.16 Å. In the eighth 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 0–5°. In the ninth 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 0–5°. There are two shorter (2.14 Å) and two longer (2.15 Å) O–Mg bond lengths. In the tenth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg5Si octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. The O–Mg bond length is 2.13 Å. In the eleventh O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg5Si octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are two shorter (2.13 Å) and two longer (2.14 Å) O–Mg bond lengths. 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 0–7°. There are two shorter (2.15 Å) and one longer (2.29 Å) O–Mg bond lengths. In the thirteenth O site, O is bonded to five Mg and one Si atom to form OMg5Si octahedra that share corners with six OMg5Al octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–7°. Both O–Mg bond lengths are 2.16 Å. In the fourteenth O site, O is bonded to five Mg and one Si atom to form OMg5Si octahedra that share corners with six OMg5Al octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–7°. There are two shorter (2.15 Å) and two longer (2.16 Å) O–Mg bond lengths. In the fifteenth 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 0–5°. There are two shorter (2.14 Å) and one longer (2.16 Å) O–Mg bond lengths. In the sixteenth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six OMg5Si octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. Both O–Mg bond lengths are 2.13 Å. In the seventeenth 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 0–5°. There are a spread of O–Mg bond distances ranging from 2.14–2.16 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2Al2SiO9 by Materials Project

Mg2Al2SiO9 crystallizes in the monoclinic P2_1 space group. The structure is two-dimensional and consists of two Mg2Al2SiO9 sheets oriented in the (0, 1, 0) direction. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share a cornercorner with one AlO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, edges with three equivalent MgO6 octahedra, and edges with three equivalent AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.23 Å. In the second Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share a cornercorner with one AlO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, edges with three equivalent MgO6 octahedra, and edges with three equivalent AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.22 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to six O atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, and edges with six MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.85–2.01 Å. In the second Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share a cornercorner with one AlO6 octahedra, corners with two MgO6 octahedra, and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–63°. There are a spread of Al–O bond distances ranging from 1.73–1.80 Å. Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO6 octahedra, corners with two MgO6 octahedra, and corners with three equivalent AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–60°. There is three shorter (1.62 Å) and one longer (1.68 Å) Si–O bond length. There are nine inequivalent O sites. In the first O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In the second O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In the third O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In the fourth O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In the fifth O site, O is bonded in a rectangular see-saw-like geometry to two Mg, one Al, and one Si atom. In the sixth O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the seventh O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the eighth O site, O is bonded in a distorted bent 150 degrees geometry to one Al and one Si atom. In the ninth O site, O is bonded in a distorted rectangular see-saw-like geometry to two Mg and two Al atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgAl2SiO7 by Materials Project

MgAl2SiO7 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with two equivalent SiO4 tetrahedra, edges with three equivalent MgO6 octahedra, and edges with three equivalent AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.08–2.16 Å. There are four inequivalent Al sites. In the first Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with four equivalent SiO4 tetrahedra and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.81–1.98 Å. In the second Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with four equivalent SiO4 tetrahedra and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.81–1.99 Å. In the third Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with two equivalent SiO4 tetrahedra and edges with six equivalent MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.87–2.07 Å. In the fourth Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with four equivalent SiO4 tetrahedra and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–1.97 Å. Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent MgO6 octahedra and corners with seven AlO6 octahedra. The corner-sharing octahedra tilt angles range from 53–60°. There is two shorter (1.65 Å) and two longer (1.66 Å) Si–O bond length. There are seven inequivalent O sites. In the first O site, O is bonded to two equivalent Mg, one Al, and one Si atom to form a mixture of distorted corner and edge-sharing OMg2AlSi tetrahedra. In the second O site, O is bonded in a distorted trigonal planar geometry to two Al and one Si atom. In the third O site, O is bonded in a trigonal non-coplanar geometry to two equivalent Mg and one Al atom. In the fourth O site, O is bonded in a trigonal non-coplanar geometry to two equivalent Mg and one Al atom. In the fifth O site, O is bonded in a distorted trigonal non-coplanar geometry to three Al atoms. In the sixth O site, O is bonded in a distorted trigonal planar geometry to two Al and one Si atom. In the seventh O site, O is bonded in a distorted trigonal planar geometry to two Al and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgAlSi4O15 by Materials Project

MgAlSi4O13O2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional and consists of eight water molecules and one MgAlSi4O13 framework. In the MgAlSi4O13 framework, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with four SiO4 tetrahedra and an edgeedge with one MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 1.98–2.08 Å. Al is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Al–O bond distances ranging from 1.80–2.18 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 57°. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra and corners with three SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. There are a spread of Si–O bond distances ranging from 1.62–1.65 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a linear geometry to two equivalent Si atoms. In the second O site, O is bonded in a 3-coordinate geometry to two equivalent Mg and one O atom. The O–O bond length is 1.38 Å. In the third O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the fourth O site, O is bonded in a bent 120 degrees geometry to two Si atoms. In the fifth O site, O is bonded in a bent 120 degrees geometry to two Si atoms. In the sixth O site, O is bonded in a 2-coordinate geometry to one Al and one O atom. The O–O bond length is 1.29 Å. In the seventh O site, O is bonded in a distorted trigonal planar geometry to one Mg, one Al, and one Si atom. In the eighth O site, O is bonded in a distorted trigonal planar geometry to one Mg, one Al, and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgAlSi4O15 by Materials Project

MgAlSi4O13O2 crystallizes in the orthorhombic Pmna space group. The structure is three-dimensional and consists of four molecular oxygen molecules and one MgAlSi4O13 framework. In the MgAlSi4O13 framework, Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four SiO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with two equivalent AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.02–2.07 Å. Al is bonded to six O atoms to form AlO6 octahedra that share corners with four SiO4 tetrahedra and edges with two equivalent MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.85–1.96 Å. There are two inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra, a cornercorner with one AlO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–58°. There are a spread of Si–O bond distances ranging from 1.63–1.65 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra, a cornercorner with one AlO6 octahedra, and corners with three SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 48–57°. There is one shorter (1.61 Å) and three longer (1.64 Å) Si–O bond length. There are eight inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Al atom. In the second O site, O is bonded in a bent 120 degrees geometry to two equivalent Mg atoms. In the third O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the fourth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the fifth O site, O is bonded in a bent 120 degrees geometry to two Si atoms. In the sixth O site, O is bonded in a linear geometry to two equivalent Si atoms. In the seventh O site, O is bonded in a distorted trigonal planar geometry to one Mg, one Al, and one Si atom. In the eighth O site, O is bonded in a distorted trigonal planar geometry to one Mg, one Al, and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg3Al(SiO4)3 by Materials Project

Mg3Al(SiO4)3 crystallizes in the monoclinic Cc space group. The structure is two-dimensional and consists of two Mg3Al(SiO4)3 sheets oriented in the (0, 0, 1) direction. there are three inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.07–2.14 Å. In the second Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.01–2.12 Å. In the third Mg site, Mg is bonded to six O atoms to form MgO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, and edges with six MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.03–2.18 Å. Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with three MgO6 octahedra and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 60–62°. There are a spread of Al–O bond distances ranging from 1.73–1.80 Å. There are three inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 57–58°. There is two shorter (1.65 Å) and two longer (1.66 Å) Si–O bond length. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–58°. There is two shorter (1.65 Å) and two longer (1.66 Å) Si–O bond length. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with three equivalent AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–59°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. There are twelve inequivalent O sites. In the first O site, O is bonded in a trigonal non-coplanar geometry to three Mg atoms. In the second O site, O is bonded in a trigonal non-coplanar geometry to three Mg atoms. In the third O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the fourth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the fifth O site, O is bonded in a distorted tetrahedral geometry to three Mg and one Al atom. In the sixth O site, O is bonded in a rectangular see-saw-like geometry to three Mg and one Si atom. In the seventh O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the eighth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the ninth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Mg and one Si atom. In the tenth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Mg and one Si atom. In the eleventh O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the twelfth O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2Al3(SiO3)6 by Materials Project

(MgAl(SiO3)3)2Al crystallizes in the orthorhombic Cccm space group. The structure is three-dimensional and consists of four aluminum molecules and one MgAl(SiO3)3 framework. In the MgAl(SiO3)3 framework, Mg is bonded to six O atoms to form distorted MgO6 pentagonal pyramids that share corners with four SiO4 tetrahedra and faces with two equivalent AlO6 pentagonal pyramids. There are two shorter (1.89 Å) and four longer (2.13 Å) Mg–O bond lengths. Al is bonded to six O atoms to form distorted AlO6 pentagonal pyramids that share corners with four SiO4 tetrahedra and faces with two equivalent MgO6 pentagonal pyramids. There are a spread of Al–O bond distances ranging from 1.91–2.01 Å. There are three inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent MgO6 pentagonal pyramids, corners with two equivalent AlO6 pentagonal pyramids, and a cornercorner with one SiO4 tetrahedra. There is three shorter (1.64 Å) and one longer (1.78 Å) Si–O bond length. In the second Si site, Si is bonded in a water-like geometry to two O atoms. Both Si–O bond lengths are 1.64 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent MgO6 pentagonal pyramids, corners with two equivalent AlO6 pentagonal pyramids, and a cornercorner with one SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.64–1.77 Å. There are six inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to one Mg, one Al, and one Si atom. In the second O site, O is bonded in a distorted linear geometry to two Si atoms. In the third O site, O is bonded in a 2-coordinate geometry to one Mg and one Al atom. In the fourth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the fifth O site, O is bonded in a bent 150 degrees geometry to two Si atoms. In the sixth O site, O is bonded in a distorted trigonal planar geometry to one Mg, one Al, and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg14AlSiO16 by Materials Project

Mg14AlSiO16 crystallizes in the orthorhombic Pmmm 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 2.11–2.18 Å. In the second 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 a spread of Mg–O bond distances ranging from 2.01–2.28 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 AlO6 octahedra, and edges with eight MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–24°. There are a spread of Mg–O bond distances ranging from 2.11–2.23 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 0–3°. There are a spread of Mg–O bond distances ranging from 2.11–2.23 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 AlO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. There are a spread of Mg–O bond distances ranging from 2.11–2.24 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 0–5°. There are a spread of Mg–O bond distances ranging from 2.10–2.22 Å. In the seventh 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 0–5°. There are a spread of Mg–O bond distances ranging from 2.10–2.22 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 AlO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 1–25°. There are a spread of Mg–O bond distances ranging from 2.11–2.24 Å. Al is bonded to six O atoms to form AlO6 octahedra that share 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 Al–O bond distances ranging from 1.77–2.11 Å. Si is bonded in a square co-planar geometry to four O atoms. There are two shorter (2.11 Å) and two longer (2.22 Å) Si–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 OMg5Al octahedra that share corners with six OMg5Al octahedra, edges with ten OMg6 octahedra, and edges with two equivalent OMg4Al square pyramids. The corner-sharing octahedra tilt angles range from 0–3°. In the second O site, O is bonded to five Mg and one Si atom to form OMg5Si octahedra that share corners with six OMg5Al octahedra, corners with two equivalent OMg4Al square pyramids, and edges with ten OMg4Si2 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. In the third O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with six equivalent OMg6 octahedra, edges with ten OMg5Al octahedra, and edges with two equivalent OMg4Al square pyramids. The corner-sharing octahedra tilt angles range from 0–1°. In the fourth O site, O is bonded to four Mg and two equivalent Al atoms to form OMg4Al2 octahedra that share corners with six OMg4Al2 octahedra, edges with eight OMg5Al octahedra, and edges with four equivalent OMg4Al square pyramids. The corner-sharing octahedral tilt angles are 0°. In the fifth O site, O is bonded to four Mg and two equivalent Si atoms to form OMg4Si2 octahedra that share corners with six OMg4Al2 octahedra, corners with four equivalent OMg4Al square pyramids, and edges with eight OMg5Si 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 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 eighth O site, O is bonded to four Mg and one Al atom to form distorted OMg4Al square pyramids that share corners with six OMg5Si octahedra, corners with three equivalent OMg4Al square pyramids, and edges with eight OMg5Al octahedra. The corner-sharing octahedra tilt angles range from 14–78°. In the ninth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with four equivalent OMg6 octahedra, corners with two equivalent OMg4Al square pyramids, and edges with twelve OMg5Al octahedra. The corner-sharing octahedra tilt angles range from 0–3°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg14AlSiO16 by Materials Project

Mg14AlSiO16 is Molybdenum Carbide MAX Phase-derived structured and crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are seven 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 MgO6 octahedra, corners with two equivalent AlO6 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 Mg–O bond distances ranging from 2.02–2.35 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 0–10°. There are four shorter (2.16 Å) and two longer (2.17 Å) Mg–O bond lengths. 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 SiO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are a spread of Mg–O bond distances ranging from 2.14–2.18 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 SiO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are a spread of Mg–O bond distances ranging from 2.14–2.18 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 SiO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–6°. There are a spread of Mg–O bond distances ranging from 2.14–2.18 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 0–6°. There are a spread of Mg–O bond distances ranging from 2.14–2.18 Å. In the seventh 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 AlO6 octahedra, an edgeedge with one SiO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–10°. There are a spread of Mg–O bond distances ranging from 2.15–2.17 Å. 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 (1.98 Å) and two longer (2.15 Å) Al–O bond lengths. Si is bonded to six O atoms to form SiO6 octahedra that share corners with two equivalent SiO6 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 (2.15 Å) and four longer (2.30 Å) Si–O bond lengths. There are ten 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 0–10°. There are two shorter (2.16 Å) and one longer (2.35 Å) O–Mg bond lengths. In the second O site, O is bonded to five Mg and one Si atom to form OMg5Si octahedra that share corners with six OMg5Al octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–9°. In the third O site, O is bonded to five Mg and one Si atom to form OMg5Si octahedra that share corners with six OMg5Al octahedra and edges with twelve OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–9°. Both O–Mg bond lengths are 2.16 Å. 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 0–2°. 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 OMg5Si 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 OMg6 octahedra and edges with twelve OMg5Si octahedra. The corner-sharing octahedral tilt angles are 0°. In the eighth 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 0–10°. In the ninth O site, O is bonded to five Mg and one Si atom to form a mixture of edge and corner-sharing OMg5Si octahedra. The corner-sharing octahedra tilt angles range from 0–9°. The O–Mg bond length is 2.02 Å. In the tenth O site, O is bonded to five Mg and one Si atom to form a mixture of edge and corner-sharing OMg5Si octahedra. The corner-sharing octahedra tilt angles range from 0–9°. There are one shorter (2.02 Å) and two longer (2.16 Å) O–Mg bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg3Al7(Si2O11)2 by Materials Project

Mg3Al7(Si2O11)2 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are four inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with four SiO4 tetrahedra and edges with six AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.01–2.19 Å. In the second Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with four SiO4 tetrahedra and edges with six AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.03–2.23 Å. In the third Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share a cornercorner with one MgO6 octahedra, corners with three SiO4 tetrahedra, edges with three AlO6 octahedra, and an edgeedge with one AlO4 tetrahedra. The corner-sharing octahedral tilt angles are 34°. There are a spread of Mg–O bond distances ranging from 2.06–2.23 Å. In the fourth Mg site, Mg is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Mg–O bond distances ranging from 1.99–2.35 Å. There are five inequivalent Al sites. In the first Al site, Al is bonded to six O atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, edges with two MgO6 octahedra, and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.74–2.12 Å. In the second Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with two equivalent AlO4 tetrahedra, corners with two SiO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.85–2.03 Å. In the third Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with two equivalent AlO6 octahedra, a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, edges with two MgO6 octahedra, and edges with four AlO6 octahedra. The corner-sharing octahedra tilt angles range from 39–44°. There are a spread of Al–O bond distances ranging from 1.81–2.04 Å. In the fourth Al site, Al is bonded to six O atoms to form distorted AlO6 octahedra that share corners with two equivalent AlO6 octahedra, a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, an edgeedge with one MgO6 octahedra, and edges with three AlO6 octahedra. The corner-sharing octahedra tilt angles range from 41–44°. There are a spread of Al–O bond distances ranging from 1.82–2.26 Å. In the fifth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with seven AlO6 octahedra, a cornercorner with one SiO4 tetrahedra, and an edgeedge with one MgO6 octahedra. The corner-sharing octahedra tilt angles range from 18–65°. There are a spread of Al–O bond distances ranging from 1.69–1.80 Å. There are five inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra, corners with three AlO6 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 45–55°. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra, corners with three AlO6 octahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 44–57°. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with four MgO6 octahedra, corners with four equivalent AlO6 octahedra, and corners with two equivalent AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–60°. There is two shorter (1.60 Å) and two longer (1.67 Å) Si–O bond length. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent MgO6 octahedra, corners with four equivalent AlO6 octahedra, and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–61°. There is two shorter (1.63 Å) and two longer (1.64 Å) Si–O bond length. In the fifth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with seven AlO6 octahedra and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 11–61°. There are a spread of Si–O bond distances ranging from 1.59–1.71 Å. There are twenty inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to one Mg, one Al, and one Si atom. In the second O site, O is bonded in a 3-coordinate geometry to one Mg, one Al, and one Si atom. In the third O site, O is bonded in a distorted T-shaped geometry to one Mg and two Al atoms. In the fourth O site, O is bonded in a distorted T-shaped geometry to one Mg, one Al, and one Si atom. In the fifth O site, O is bonded in a bent 150 degrees geometry to two equivalent Mg atoms. In the sixth O site, O is bonded in a bent 150 degrees geometry to two equivalent Mg atoms. In the seventh O site, O is bonded to one Mg and three Al atoms to form distorted OMgAl3 tetrahedra that share corners with three OMgAl3 tetrahedra, corners with five OMgAl3 trigonal pyramids, and edges with two equivalent OMgAl2Si trigonal pyramids. In the eighth O site, O is bonded to one Mg and three Al atoms to form distorted OMgAl3 trigonal pyramids that share corners with three OMgAl3 tetrahedra, corners with three OMgAl3 trigonal pyramids, edges with two equivalent OAl4 tetrahedra, and edges with two equivalent OMgAl2Si trigonal pyramids. In the ninth O site, O is bonded to one Mg, two equivalent Al, and one Si atom to form distorted OMgAl2Si trigonal pyramids that share corners with two equivalent OAl4 tetrahedra, corners with four OMgAl3 trigonal pyramids, edges with two equivalent OMgAl3 tetrahedra, and an edgeedge with one OMgAl2Si trigonal pyramid. In the tenth O site, O is bonded to one Mg, two equivalent Al, and one Si atom to form distorted OMgAl2Si trigonal pyramids that share corners with four OMgAl3 tetrahedra, corners with two equivalent OMgAl2Si trigonal pyramids, and edges with three OMgAl2Si trigonal pyramids. In the eleventh O site, O is bonded to one Mg and three Al atoms to form corner-sharing OMgAl3 trigonal pyramids. In the twelfth O site, O is bonded to one Mg and three Al atoms to form OMgAl3 tetrahedra that share corners with three OMgAl3 trigonal pyramids and edges with two equivalent OAl4 tetrahedra. In the thirteenth O site, O is bonded in a distorted trigonal planar geometry to one Mg, one Al, and one Si atom. In the fourteenth O site, O is bonded in a distorted trigonal planar geometry to one Mg and two Si atoms. In the fifteenth O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the sixteenth O site, O is bonded in a bent 150 degrees geometry to two equivalent Si atoms. In the seventeenth O site, O is bonded in a distorted rectangular see-saw-like geometry to three Al and one Si atom. In the eighteenth O site, O is bonded to four Al atoms to form distorted OAl4 tetrahedra that share corners with three OMgAl3 tetrahedra, corners with three OMgAl2Si trigonal pyramids, an edgeedge with one OMgAl3 tetrahedra, and an edgeedge with one OMgAl3 trigonal pyramid. In the nineteenth O site, O is bonded in a distorted trigonal planar geometry to one Mg, one Al, and one Si atom. In the twentieth O site, O is bonded in a distorted trigonal planar geometry to one Mg, one Al, and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg30AlSiO32 by Materials Project

Mg30AlSiO32 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 2.12–2.17 Å. In the second 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 a spread of Mg–O bond distances ranging from 2.02–2.20 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 four shorter (2.13 Å) and two 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 (2.11 Å) and two longer (2.18 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 AlO6 octahedra, and edges with ten MgO6 octahedra. The corner-sharing octahedra tilt angles range from 0–22°. There are a spread of Mg–O bond distances ranging from 2.12–2.17 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 0–2°. There are a spread of Mg–O bond distances ranging from 2.12–2.17 Å. 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 0–3°. There are four shorter (2.12 Å) and two longer (2.17 Å) Mg–O bond lengths. In the eighth 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 0–5°. There are a spread of Mg–O bond distances ranging from 2.11–2.17 Å. Al is bonded to six O atoms to form AlO6 octahedra that share corners with four equivalent MgO6 octahedra and edges with twelve MgO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There is two shorter (1.77 Å) and four longer (2.08 Å) Al–O bond length. Si is bonded in a square co-planar geometry to four equivalent O atoms. All Si–O bond lengths are 2.22 Å. There are eleven 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, edges with ten OMg5Al octahedra, and edges with two equivalent OMg4Al square pyramids. The corner-sharing octahedra tilt angles range from 0–2°. In the second O site, O is bonded to five Mg and one Si atom to form OMg5Si octahedra that share corners with six OMg5Si octahedra, corners with two equivalent OMg4Al square pyramids, and edges with ten OMg6 octahedra. The corner-sharing octahedra tilt angles range from 0–3°. In the third 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°. Both O–Mg bond lengths are 2.17 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 0–3°. In the fifth 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°. There are two shorter (2.12 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 equivalent OMg6 octahedra, edges with eleven OMg5Al octahedra, and an edgeedge with one OMg4Al square pyramid. The corner-sharing octahedra tilt angles range from 0–1°. In the seventh O site, O is bonded to four equivalent Mg and one Al atom to form distorted OMg4Al square pyramids that share corners with eight OMg5Si octahedra, a cornercorner with one OMg4Al square pyramid, and edges with eight OMg5Al octahedra. The corner-sharing octahedra tilt angles range from 12–76°. In the eighth O site, O is bonded to six Mg atoms to form OMg6 octahedra that share corners with four OMg6 octahedra, corners with two equivalent OMg4Al square pyramids, and edges with twelve OMg5Al octahedra. The corner-sharing octahedra tilt angles range from 0–1°. In the ninth 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 0–1°. In the tenth 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°. The O–Mg bond length is 2.12 Å. 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°. There are three shorter (2.12 Å) and two longer (2.17 Å) O–Mg bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MgAl2SiO7 by Materials Project

MgAl2SiO7 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Mg is bonded to six O atoms to form distorted MgO6 octahedra that share corners with two equivalent SiO4 tetrahedra, edges with three equivalent MgO6 octahedra, and edges with three equivalent AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.07–2.17 Å. There are three inequivalent Al sites. In the first Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with four equivalent SiO4 tetrahedra and edges with four AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–1.98 Å. In the second Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with two equivalent SiO4 tetrahedra and edges with six equivalent MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.86–2.07 Å. In the third Al site, Al is bonded to six O atoms to form AlO6 octahedra that share corners with four equivalent SiO4 tetrahedra and edges with four equivalent AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.82–1.98 Å. Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent MgO6 octahedra and corners with seven AlO6 octahedra. The corner-sharing octahedra tilt angles range from 53–60°. There is three shorter (1.65 Å) and one longer (1.66 Å) Si–O bond length. There are seven inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to two Al and one Si atom. In the second O site, O is bonded in a distorted trigonal planar geometry to two equivalent Al and one Si atom. In the third O site, O is bonded in a distorted trigonal non-coplanar geometry to three Al atoms. In the fourth O site, O is bonded to two equivalent Mg, one Al, and one Si atom to form a mixture of distorted corner and edge-sharing OMg2AlSi trigonal pyramids. In the fifth O site, O is bonded in a trigonal non-coplanar geometry to two equivalent Mg and one Al atom. In the sixth O site, O is bonded in a trigonal non-coplanar geometry to two equivalent Mg and one Al atom. In the seventh O site, O is bonded in a distorted trigonal planar geometry to two Al and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2Al2SiO9 by Materials Project

Mg2Al2SiO9 crystallizes in the triclinic P1 space group. The structure is two-dimensional and consists of two Mg2Al2SiO9 sheets oriented in the (0, 0, 1) direction. there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share a cornercorner with one AlO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, edges with three equivalent MgO6 octahedra, and edges with three equivalent AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.20 Å. In the second Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share a cornercorner with one AlO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, edges with three equivalent MgO6 octahedra, and edges with three equivalent AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.25 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share a cornercorner with one AlO6 octahedra, corners with two MgO6 octahedra, and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–63°. There are a spread of Al–O bond distances ranging from 1.74–1.81 Å. In the second Al site, Al is bonded to six O atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, and edges with six MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.85–1.98 Å. Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO6 octahedra, corners with two MgO6 octahedra, and corners with three equivalent AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 53–61°. There is three shorter (1.62 Å) and one longer (1.69 Å) Si–O bond length. There are nine inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the second O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In the third O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In the fourth O site, O is bonded in a distorted rectangular see-saw-like geometry to two Mg and two Al atoms. In the fifth O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In the sixth O site, O is bonded in a bent 120 degrees geometry to one Al and one Si atom. In the seventh O site, O is bonded in a rectangular see-saw-like geometry to two Mg, one Al, and one Si atom. In the eighth O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the ninth O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg2Al2SiO9 by Materials Project

Mg2Al2SiO9 crystallizes in the triclinic P1 space group. The structure is two-dimensional and consists of two Mg2Al2SiO9 sheets oriented in the (0, 0, 1) direction. In one of the Mg2Al2SiO9 sheets, there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share a cornercorner with one AlO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, edges with three equivalent MgO6 octahedra, and edges with three equivalent AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.24 Å. In the second Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share a cornercorner with one AlO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, edges with three equivalent MgO6 octahedra, and edges with three equivalent AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.21 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share a cornercorner with one AlO6 octahedra, corners with two MgO6 octahedra, and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 55–63°. There are a spread of Al–O bond distances ranging from 1.73–1.80 Å. In the second Al site, Al is bonded to six O atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, and edges with six MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.86–2.02 Å. Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO6 octahedra, corners with two MgO6 octahedra, and corners with three equivalent AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–60°. There are a spread of Si–O bond distances ranging from 1.61–1.69 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a distorted rectangular see-saw-like geometry to two Mg and two Al atoms. In the second O site, O is bonded in a distorted bent 120 degrees geometry to one Al and one Si atom. In the third O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the fourth O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the fifth O site, O is bonded in a rectangular see-saw-like geometry to two Mg, one Al, and one Si atom. In the sixth O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In the seventh O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In the eighth O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In the ninth O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In one of the Mg2Al2SiO9 sheets, there are two inequivalent Mg sites. In the first Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share a cornercorner with one AlO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, edges with three equivalent MgO6 octahedra, and edges with three equivalent AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.24 Å. In the second Mg site, Mg is bonded to six O atoms to form distorted MgO6 octahedra that share a cornercorner with one AlO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, edges with three equivalent MgO6 octahedra, and edges with three equivalent AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.23 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share a cornercorner with one AlO6 octahedra, corners with two MgO6 octahedra, and corners with three equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 56–63°. There is three shorter (1.74 Å) and one longer (1.79 Å) Al–O bond length. In the second Al site, Al is bonded to six O atoms to form AlO6 octahedra that share a cornercorner with one AlO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, and edges with six MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.86–2.01 Å. Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO6 octahedra, corners with two MgO6 octahedra, and corners with three equivalent AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 54–60°. There is three shorter (1.62 Å) and one longer (1.69 Å) Si–O bond length. There are nine inequivalent O sites. In the first O site, O is bonded in a distorted bent 150 degrees geometry to one Al and one Si atom. In the second O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the third O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the fourth O site, O is bonded in a distorted rectangular see-saw-like geometry to two Mg and two Al atoms. In the fifth O site, O is bonded in a rectangular see-saw-like geometry to two Mg, one Al, and one Si atom. In the sixth O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In the seventh O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In the eighth O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom. In the ninth O site, O is bonded in a trigonal non-coplanar geometry to two Mg and one Al atom.

36 MATERIALS SCIENCE↗