Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “Al-Ca-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.

8 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Ca2MgAl2(SiO4)3 by Materials Project

Ca2MgAl2(SiO4)3 is Esseneite-derived structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.36–2.76 Å. In the second Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.70 Å. Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra, an edgeedge with one MgO6 octahedra, and an edgeedge with one AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.16 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with three equivalent AlO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 33–62°. There are a spread of Al–O bond distances ranging from 1.74–1.81 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with three equivalent AlO4 tetrahedra, corners with three SiO4 tetrahedra, an edgeedge with one MgO6 octahedra, and an edgeedge with one AlO6 octahedra. There are a spread of Al–O bond distances ranging from 1.85–2.10 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 three equivalent MgO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–59°. There are a spread of Si–O bond distances ranging from 1.61–1.70 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one AlO6 octahedra, corners with two equivalent MgO6 octahedra, a cornercorner with one AlO4 tetrahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–60°. There are a spread of Si–O bond distances ranging from 1.61–1.71 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra, corners with two equivalent AlO6 octahedra, a cornercorner with one AlO4 tetrahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 34–62°. There are a spread of Si–O bond distances ranging from 1.63–1.68 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Al3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ca2+, one Al3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two equivalent Mg2+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ca2+ and two Si4+ atoms. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+ and two Al3+ atoms. In the eleventh O2- site, O2- is bonded to one Ca2+ and three Al3+ atoms to form distorted edge-sharing OCaAl3 tetrahedra. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca16MgAl14Si9O56 by Materials Project

Ca16MgAl14Si9O56 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are sixteen inequivalent Ca sites. In the first Ca site, Ca is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Ca–O bond distances ranging from 2.31–2.65 Å. In the second Ca site, Ca is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Ca–O bond distances ranging from 2.25–2.50 Å. In the third Ca site, Ca is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Ca–O bond distances ranging from 2.26–2.84 Å. In the fourth Ca site, Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.35–3.00 Å. In the fifth Ca site, Ca is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Ca–O bond distances ranging from 2.22–2.74 Å. In the sixth Ca site, Ca is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Ca–O bond distances ranging from 2.19–2.89 Å. In the seventh Ca site, Ca is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Ca–O bond distances ranging from 2.25–2.94 Å. In the eighth Ca site, Ca is bonded in a distorted pentagonal planar geometry to five O atoms. There are a spread of Ca–O bond distances ranging from 2.24–2.38 Å. In the ninth Ca site, Ca is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Ca–O bond distances ranging from 2.29–2.71 Å. In the tenth Ca site, Ca is bonded to four O atoms to form distorted CaO4 trigonal pyramids that share a cornercorner with one AlO4 tetrahedra and corners with three SiO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.23–2.44 Å. In the eleventh Ca site, Ca is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Ca–O bond distances ranging from 2.22–2.98 Å. In the twelfth Ca site, Ca is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of Ca–O bond distances ranging from 2.38–3.11 Å. In the thirteenth Ca site, Ca is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Ca–O bond distances ranging from 2.28–2.80 Å. In the fourteenth Ca site, Ca is bonded in a 5-coordinate geometry to five O atoms. There are a spread of Ca–O bond distances ranging from 2.33–2.67 Å. In the fifteenth Ca site, Ca is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Ca–O bond distances ranging from 2.23–2.80 Å. In the sixteenth Ca site, Ca is bonded in a 4-coordinate geometry to five O atoms. There are a spread of Ca–O bond distances ranging from 2.29–2.83 Å. Mg is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Mg–O bond distances ranging from 1.97–2.62 Å. There are fourteen inequivalent Al sites. In the first Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with two AlO4 tetrahedra and corners with two SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.75–1.81 Å. In the second Al site, Al is bonded to five O atoms to form AlO5 trigonal bipyramids that share corners with three SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.80–2.02 Å. In the third Al site, Al is bonded in a 4-coordinate geometry to five O atoms. There are a spread of Al–O bond distances ranging from 1.76–2.38 Å. In the fourth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with two AlO4 tetrahedra and corners with two SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.73–1.80 Å. In the fifth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with two AlO4 tetrahedra and corners with two SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.73–1.79 Å. In the sixth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.75–1.80 Å. In the seventh Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with two AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.75–1.79 Å. In the eighth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with two AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.73–1.79 Å. In the ninth Al site, Al is bonded in a distorted trigonal non-coplanar geometry to three O atoms. There are a spread of Al–O bond distances ranging from 1.83–1.90 Å. In the tenth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with two AlO4 tetrahedra. There is one shorter (1.75 Å) and three longer (1.79 Å) Al–O bond length. In the eleventh Al site, Al is bonded to four O atoms to form distorted AlO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and a cornercorner with one CaO4 trigonal pyramid. There are a spread of Al–O bond distances ranging from 1.75–1.81 Å. In the twelfth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and corners with two AlO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.74–1.78 Å. In the thirteenth Al site, Al is bonded in a 4-coordinate geometry to five O atoms. There are a spread of Al–O bond distances ranging from 1.76–2.40 Å. In the fourteenth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with two AlO4 tetrahedra and corners with two SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.76–1.82 Å. There are nine inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two AlO4 tetrahedra and a cornercorner with one AlO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and a cornercorner with one AlO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.61–1.72 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one SiO4 tetrahedra and a cornercorner with one CaO4 trigonal pyramid. There are a spread of Si–O bond distances ranging from 1.61–1.73 Å. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the fifth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the sixth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and a cornercorner with one AlO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the seventh Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with two equivalent CaO4 trigonal pyramids. There are a spread of Si–O bond distances ranging from 1.60–1.68 Å. In the eighth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with three AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.63–1.66 Å. In the ninth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.66 Å. There are fifty-six inequivalent O sites. In the first O site, O is bonded in a distorted bent 120 degrees geometry to two Ca, one Al, and one Si atom. In the second O site, O is bonded in a 3-coordinate geometry to two Ca and one Si atom. In the third O site, O is bonded in a distorted trigonal planar geometry to one Ca, one Al, and one Si atom. In the fourth O site, O is bonded in a distorted bent 120 degrees geometry to two Ca, one Al, and one Si atom. In the fifth O site, O is bonded in a 5-coordinate geometry to three Ca, one Mg, and one O atom. The O–O bond length is 1.54 Å. In the sixth O site, O is bonded in a distorted bent 120 degrees geometry to one Ca, one Mg, and one Si atom. In the seventh O site, O is bonded to two Ca and two Al atoms to form distorted edge-sharing OCa2Al2 tetrahedra. In the eighth O site, O is bonded in a trigonal planar geometry to one Ca, one Al, and one Si atom. In the ninth O site, O is bonded to three Ca and one Al atom to form a mixture of distorted edge and corner-sharing OCa3Al tetrahedra. In the tenth O site, O is bonded in a distorted trigonal planar geometry to one Ca, one Al, and one Si atom. In the eleventh O site, O is bonded in a 2-coordinate geometry to two Ca and two Al atoms. In the twelfth O site, O is bonded in a 4-coordinate geometry to two Ca and two Al atoms. In the thirteenth O site, O is bonded to three Ca and one Si atom to form distorted edge-sharing OCa3Si trigonal pyramids. In the fourteenth O site, O is bonded in a 1-coordinate geometry to four Ca and one Si atom. In the fifteenth O site, O is bonded to two Ca and two Al atoms to form a mixture of distorted edge and corner-sharing OCa2Al2 trigonal pyramids. In the sixteenth O site, O is bonded in a 4-coordinate geometry to two Ca, one Al, and one Si atom. In the seventeenth O site, O is bonded in a 1-coordinate geometry to three Ca and one Si atom. In the eighteenth O site, O is bonded to two Ca and two Al atoms to form a mixture of distorted edge and corner-sharing OCa2Al2 tetrahedra. In the nineteenth O site, O is bonded in a bent 150 degrees geometry to one Al and one Si atom. In the twentieth O site, O is bonded to three Ca and one Al atom to form distorted OCa3Al trigonal pyramids that share corners with two equivalent OCa3Al tetrahedra and an edgeedge with one OCa2Al2 trigonal pyramid. In the twenty-first O site, O is bonded in a distorted trigonal non-coplanar geometry to two Ca and one Si atom. In the twenty-second O site, O is bonded in a 4-coordinate geometry to one Ca, one Mg, one Al, and one O atom. In the twenty-third O site, O is bonded in a trigonal planar geometry to one Ca, one Al, and one Si atom. In the twenty-fourth O site, O is bonded in a distorted trigonal planar geometry to one Ca, one Al, and one Si atom. In the twenty-fifth O site, O is bonded in a 2-coordinate geometry to one Ca, two Al, and one Si atom. In the twenty-sixth O site, O is bonded in a 3-coordinate geometry to one Ca, one Al, and one Si atom. In the twenty-seventh O site, O is bonded in a bent 120 degrees geometry to two Al atoms. In the twenty-eighth O site, O is bonded in a bent 120 degrees geometry to one Ca and two Al atoms. In the twenty-ninth O site, O is bonded in a distorted trigonal planar geometry to one Ca, one Al, and one Si atom. In the thirtieth O site, O is bonded in a 2-coordinate geometry to one Ca, one Al, and one Si atom. In the thirty-first O site, O is bonded in a distorted T-shaped geometry to one Ca and two Al atoms. In the thirty-second O site, O is bonded in a 3-coordinate geometry to one Ca, one Mg, and two Si atoms. In the thirty-third O site, O is bonded in a 3-coordinate geometry to one Ca, one Al, and one Si atom. In the thirty-fourth O site, O is bonded in a distorted water-like geometry to one Ca and two Al atoms. In the thirty-fifth O site, O is bonded in a 3-coordinate geometry to one Ca, one Al, and one Si atom. In the thirty-sixth O site, O is bonded in a bent 120 degrees geometry to two Al atoms. In the thirty-seventh O site, O is bonded in a 4-coordinate geometry to two Ca and two Al atoms. In the thirty-eighth O site, O is bonded in a distorted T-shaped geometry to one Ca, on

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca6Mg5Al2Si11O36 by Materials Project

Ca6Mg5Al2Si11O36 is Esseneite-derived structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.32–2.83 Å. In the second Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.77 Å. In the third Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.76 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.76 Å. In the fifth Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.32–2.78 Å. In the sixth Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.36–2.80 Å. There are five 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 MgO6 octahedra, and an edgeedge with one AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.18 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 two MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.15 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with two MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.15 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six SiO4 tetrahedra and edges with two MgO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.06–2.14 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with five SiO4 tetrahedra, an edgeedge with one MgO6 octahedra, and an edgeedge with one AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.15 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with two equivalent AlO4 tetrahedra, corners with four SiO4 tetrahedra, and edges with two MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.86–2.10 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one MgO6 octahedra, corners with two equivalent AlO6 octahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 34–66°. There are a spread of Al–O bond distances ranging from 1.76–1.82 Å. There are eleven inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–58°. There are a spread of Si–O bond distances ranging from 1.61–1.71 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one AlO6 octahedra, corners with two equivalent MgO6 octahedra, a cornercorner with one AlO4 tetrahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 39–59°. There are a spread of Si–O bond distances ranging from 1.61–1.71 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–58°. There are a spread of Si–O bond distances ranging from 1.61–1.70 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–59°. There are a spread of Si–O bond distances ranging from 1.61–1.71 Å. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–58°. There are a spread of Si–O bond distances ranging from 1.60–1.71 Å. In the sixth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–58°. There are a spread of Si–O bond distances ranging from 1.60–1.71 Å. In the seventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 33–59°. There are a spread of Si–O bond distances ranging from 1.60–1.71 Å. In the eighth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 37–58°. There are a spread of Si–O bond distances ranging from 1.61–1.70 Å. In the ninth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one AlO6 octahedra, corners with two equivalent MgO6 octahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 31–61°. There are a spread of Si–O bond distances ranging from 1.60–1.70 Å. In the tenth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with three MgO6 octahedra, a cornercorner with one AlO4 tetrahedra, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 38–58°. There are a spread of Si–O bond distances ranging from 1.61–1.70 Å. In the eleventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one MgO6 octahedra, corners with two equivalent AlO6 octahedra, and corners with two SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 32–61°. There are a spread of Si–O bond distances ranging from 1.62–1.69 Å. There are thirty-six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Mg2+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Mg2+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Mg2+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the thirteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the fourteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Mg2+, and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Mg2+, and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the eighteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the nineteenth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the twentieth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the twenty-first O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Mg2+, and one Si4+ atom. In the twenty-second O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Mg2+, and one Si4+ atom. In the twenty-third O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the twenty-fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the twenty-fifth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the twenty-sixth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the twenty-seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the twenty-eighth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Mg2+, and one Si4+ atom. In the twenty-ninth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the thirtieth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the thirty-first O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the thirty-second O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Al3+, and one Si4+ atom. In the thirty-third O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the thirty-fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, and two Al3+ atoms. In the thirty-fifth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+ and two Al3+ atoms. In the thirty-sixth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca8MgAl6Si5O28 by Materials Project

Ca8MgAl6Si5O28 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.19–2.66 Å. In the second Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.69 Å. In the third Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to five O2- atoms. There are a spread of Ca–O bond distances ranging from 2.30–2.63 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.25–3.04 Å. In the fifth Ca2+ site, Ca2+ is bonded to seven O2- atoms to form distorted CaO7 pentagonal bipyramids that share a cornercorner with one AlO4 tetrahedra, corners with three SiO4 tetrahedra, a cornercorner with one CaO5 trigonal bipyramid, a cornercorner with one MgO5 trigonal bipyramid, and an edgeedge with one AlO5 trigonal bipyramid. There are a spread of Ca–O bond distances ranging from 2.37–2.93 Å. In the sixth Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.31–2.85 Å. In the seventh Ca2+ site, Ca2+ is bonded to five O2- atoms to form distorted CaO5 trigonal bipyramids that share a cornercorner with one CaO7 pentagonal bipyramid, a cornercorner with one SiO4 tetrahedra, corners with two AlO4 tetrahedra, a cornercorner with one AlO5 trigonal bipyramid, an edgeedge with one SiO4 tetrahedra, and an edgeedge with one AlO5 trigonal bipyramid. There are a spread of Ca–O bond distances ranging from 2.25–2.58 Å. In the eighth Ca2+ site, Ca2+ is bonded in a distorted pentagonal planar geometry to five O2- atoms. There are a spread of Ca–O bond distances ranging from 2.33–2.53 Å. Mg2+ is bonded to five O2- atoms to form distorted MgO5 trigonal bipyramids that share a cornercorner with one CaO7 pentagonal bipyramid, corners with three SiO4 tetrahedra, and an edgeedge with one AlO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 1.90–2.41 Å. There are six inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded in a rectangular see-saw-like geometry to four O2- atoms. There are a spread of Al–O bond distances ranging from 1.87–1.95 Å. In the second Al3+ site, Al3+ is bonded to five O2- atoms to form AlO5 trigonal bipyramids that share a cornercorner with one SiO4 tetrahedra, corners with two AlO4 tetrahedra, a cornercorner with one CaO5 trigonal bipyramid, and an edgeedge with one SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.80–2.00 Å. In the third Al3+ site, Al3+ is bonded to five O2- atoms to form AlO5 trigonal bipyramids that share a cornercorner with one AlO4 tetrahedra, a cornercorner with one SiO4 tetrahedra, an edgeedge with one CaO7 pentagonal bipyramid, and an edgeedge with one CaO5 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.78–2.05 Å. In the fourth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one CaO7 pentagonal bipyramid, a cornercorner with one AlO5 trigonal bipyramid, and an edgeedge with one MgO5 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.75–1.79 Å. In the fifth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two SiO4 tetrahedra, a cornercorner with one CaO5 trigonal bipyramid, and a cornercorner with one AlO5 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.75–1.79 Å. In the sixth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with two SiO4 tetrahedra, a cornercorner with one CaO5 trigonal bipyramid, and a cornercorner with one AlO5 trigonal bipyramid. There are a spread of Al–O bond distances ranging from 1.77–1.81 Å. There are five inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one CaO7 pentagonal bipyramid, corners with two AlO4 tetrahedra, and a cornercorner with one MgO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.63–1.70 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with two AlO5 trigonal bipyramids and an edgeedge with one CaO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.60–1.69 Å. In the third Si4+ site, Si4+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There are a spread of Si–O bond distances ranging from 1.67–1.75 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one CaO7 pentagonal bipyramid, corners with two AlO4 tetrahedra, and a cornercorner with one MgO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.59–1.69 Å. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one CaO7 pentagonal bipyramid, a cornercorner with one CaO5 trigonal bipyramid, a cornercorner with one MgO5 trigonal bipyramid, and an edgeedge with one AlO5 trigonal bipyramid. There are a spread of Si–O bond distances ranging from 1.62–1.70 Å. There are twenty-eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a water-like geometry to one Al3+ and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Al3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Mg2+, and one Al3+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Al3+ atoms. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Al3+ atoms. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to four Ca2+ and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 3-coordinate geometry to three Ca2+ and one Al3+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Mg2+, and one Al3+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a distorted trigonal pyramidal geometry to three Ca2+ and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a 1-coordinate geometry to three Ca2+, one Al3+, and one O2- atom. The O–O bond length is 1.51 Å. In the fourteenth O2- site, O2- is bonded in a 1-coordinate geometry to two Ca2+, one Al3+, and one O2- atom. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a 3-coordinate geometry to two Ca2+ and one Si4+ atom. In the eighteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the nineteenth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the twentieth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the twenty-first O2- site, O2- is bonded in a bent 150 degrees geometry to one Al3+ and one Si4+ atom. In the twenty-second O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Al3+ atoms. In the twenty-third O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Al3+, and one Si4+ atom. In the twenty-fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Al3+ atoms. In the twenty-fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the twenty-sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Al3+, and one Si4+ atom. In the twenty-seventh O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ca2+, one Al3+, and one Si4+ atom. In the twenty-eighth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca2MgAl2(SiO4)3 by Materials Project

Ca2MgAl2(SiO4)3 is Esseneite-derived structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.37–2.75 Å. In the second Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.32–2.74 Å. Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one AlO4 tetrahedra, corners with five SiO4 tetrahedra, and edges with two equivalent AlO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.05–2.18 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one MgO6 octahedra, corners with two equivalent AlO6 octahedra, and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 36–68°. There are a spread of Al–O bond distances ranging from 1.75–1.80 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with two equivalent AlO4 tetrahedra, corners with four SiO4 tetrahedra, and edges with two equivalent MgO6 octahedra. There are a spread of Al–O bond distances ranging from 1.87–2.08 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 a cornercorner with one MgO6 octahedra, corners with two equivalent AlO6 octahedra, and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 34–61°. There are a spread of Si–O bond distances ranging from 1.62–1.70 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one AlO6 octahedra, corners with two equivalent MgO6 octahedra, and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–61°. There are a spread of Si–O bond distances ranging from 1.60–1.70 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one AlO6 octahedra, corners with two equivalent MgO6 octahedra, and corners with two equivalent AlO4 tetrahedra. The corner-sharing octahedra tilt angles range from 40–61°. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded to one Ca2+, one Mg2+, and two Al3+ atoms to form distorted edge-sharing OCaMgAl2 tetrahedra. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom to form distorted edge-sharing OCaMgAlSi tetrahedra. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+ and two Al3+ atoms. In the tenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Al3+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Mg2+, and one Si4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca4MgAl2Si3O14 by Materials Project

Ca4MgAl2Si3O14 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are four inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.28–2.89 Å. In the second Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.97 Å. In the third Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.32–2.82 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.42–2.89 Å. Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with three SiO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 1.91–1.96 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one AlO4 tetrahedra and corners with three SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.75–1.79 Å. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share a cornercorner with one MgO4 tetrahedra, a cornercorner with one AlO4 tetrahedra, and a cornercorner with one SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.74–1.78 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 a cornercorner with one MgO4 tetrahedra, a cornercorner with one AlO4 tetrahedra, and a cornercorner with one SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.69 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one MgO4 tetrahedra and corners with two AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the third Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one MgO4 tetrahedra, a cornercorner with one AlO4 tetrahedra, and a cornercorner with one SiO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.69 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Si4+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a distorted tetrahedral geometry to three Ca2+ and one Al3+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to three Ca2+ and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 1-coordinate geometry to three Ca2+ and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to three Ca2+ and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Mg2+, and one Al3+ atom. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Ca2+, one Al3+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 3-coordinate geometry to two Ca2+, one Mg2+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Ca2+, one Al3+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+, one Mg2+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Ca2+, one Al3+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Mg2+, and one Si4+ atom. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two Al3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca2MgAl2Si3O14 by Materials Project

Ca2MgAl2Si3O14 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Ca–O bond distances ranging from 2.30–2.59 Å. In the second Ca site, Ca is bonded to seven O atoms to form distorted CaO7 pentagonal bipyramids that share corners with five SiO4 tetrahedra, edges with two equivalent MgO6 octahedra, edges with two equivalent AlO6 octahedra, and an edgeedge with one SiO4 tetrahedra. There are a spread of Ca–O bond distances ranging from 2.24–2.51 Å. Mg is bonded to six O atoms to form MgO6 octahedra that share corners with four SiO4 tetrahedra, edges with two equivalent MgO6 octahedra, and edges with two equivalent CaO7 pentagonal bipyramids. There are a spread of Mg–O bond distances ranging from 1.98–2.16 Å. Al is bonded to six O atoms to form AlO6 octahedra that share corners with four SiO4 tetrahedra, edges with two equivalent AlO6 octahedra, and an edgeedge with one CaO7 pentagonal bipyramid. There are a spread of Al–O bond distances ranging from 1.86–2.08 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 octahedra, corners with four equivalent AlO6 octahedra, and corners with two equivalent CaO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 48–55°. There are a spread of Si–O bond distances ranging from 1.63–1.67 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with four equivalent AlO6 octahedra, a cornercorner with one SiO4 tetrahedra, and an edgeedge with one CaO7 pentagonal bipyramid. The corner-sharing octahedra tilt angles range from 51–55°. There are a spread of Si–O bond distances ranging from 1.62–1.67 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with two equivalent MgO6 octahedra, corners with three equivalent CaO7 pentagonal bipyramids, and a cornercorner with one SiO4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. There are a spread of Si–O bond distances ranging from 1.62–1.70 Å. There are eleven inequivalent O sites. In the first O site, O is bonded in a distorted trigonal planar geometry to one Ca, one Al, and one Si atom. In the second O site, O is bonded in a distorted rectangular see-saw-like geometry to one Ca, two equivalent Mg, and one Si atom. In the third O site, O is bonded in a trigonal non-coplanar geometry to one Ca and two equivalent Mg atoms. In the fourth O site, O is bonded in a water-like geometry to two equivalent Al atoms. In the fifth O site, O is bonded in a bent 150 degrees geometry to one Ca and one Si atom. In the sixth O site, O is bonded in a 4-coordinate geometry to two Ca, one Mg, and one Si atom. In the seventh O site, O is bonded in a water-like geometry to two equivalent Al atoms. In the eighth O site, O is bonded in a trigonal planar geometry to one Ca, one Al, and one Si atom. In the ninth O site, O is bonded in a distorted trigonal pyramidal geometry to one Ca, two equivalent Al, and one Si atom. In the tenth O site, O is bonded in a 3-coordinate geometry to one Ca and two Si atoms. In the eleventh O site, O is bonded in a 3-coordinate geometry to two equivalent Al and one Si atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ca3Mg9Al8(SiO4)12 by Materials Project

Ca3Mg9Al8(SiO4)12 is Esseneite-derived structured and crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.33–2.45 Å. In the second Ca2+ site, Ca2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.32–2.47 Å. There are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Mg–O bond distances ranging from 2.21–2.43 Å. In the second Mg2+ site, Mg2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Mg–O bond distances ranging from 2.19–2.44 Å. In the third Mg2+ site, Mg2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Mg–O bond distances ranging from 2.21–2.40 Å. In the fourth Mg2+ site, Mg2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Mg–O bond distances ranging from 2.23–2.40 Å. In the fifth Mg2+ site, Mg2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Mg–O bond distances ranging from 2.21–2.43 Å. In the sixth Mg2+ site, Mg2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Mg–O bond distances ranging from 2.22–2.42 Å. There are four inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.90–1.95 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.89–1.93 Å. In the third Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.90–1.93 Å. In the fourth Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.90–1.93 Å. There are eight inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedra tilt angles range from 45–50°. There is three shorter (1.65 Å) and one longer (1.66 Å) Si–O bond length. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedra tilt angles range from 47–50°. 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 four AlO6 octahedra. The corner-sharing octahedra tilt angles range from 49–50°. All Si–O bond lengths are 1.66 Å. In the fourth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedra tilt angles range from 47–48°. There is one shorter (1.65 Å) and three longer (1.66 Å) Si–O bond length. In the fifth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedra tilt angles range from 47–50°. There is three shorter (1.65 Å) and one longer (1.66 Å) Si–O bond length. In the sixth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedra tilt angles range from 46–48°. All Si–O bond lengths are 1.66 Å. In the seventh Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedra tilt angles range from 44–48°. All Si–O bond lengths are 1.65 Å. In the eighth Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO6 octahedra. The corner-sharing octahedra tilt angles range from 48–49°. There is one shorter (1.65 Å) and three longer (1.66 Å) Si–O bond length. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the fourteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom. In the fifteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Al3+, and one Si4+ atom. In the sixteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the seventeenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the eighteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Mg2+, one Al3+, and one Si4+ atom. In the nineteenth O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom. In the twentieth O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom. In the twenty-first O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom. In the twenty-second O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom. In the twenty-third O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom. In the twenty-fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Mg2+, one Al3+, and one Si4+ atom.

36 MATERIALS SCIENCE↗