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DOE OSTI · 1718714

Materials Data on CaAl2(SiO6)2 by Materials Project

Abstract

CaAl2(SiO6)2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first 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 2.34–2.94 Å. In the second Ca site, Ca is bonded in a 6-coordinate geometry to seven O atoms. There are a spread of Ca–O bond distances ranging from 2.35–3.05 Å. There are four inequivalent Al sites. In the first Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.74–1.78 Å. In the second Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.74–1.78 Å. In the third Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.73–1.78 Å. In the fourth Al site, Al is bonded to four O atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.73–1.78 Å. There are four inequivalent Si sites. In the first Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with four AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.60–1.68 Å. In the second Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with four AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.67 Å. In the third Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with four AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. In the fourth Si site, Si is bonded to four O atoms to form SiO4 tetrahedra that share corners with four AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.66 Å. There are twenty-four 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 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 bent 150 degrees geometry to one Al and one Si atom. In the fifth O site, O is bonded in a bent 150 degrees geometry to 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 3-coordinate geometry to one Ca, one Al, and one Si atom. In the eighth O site, O is bonded in a 2-coordinate geometry to one Ca, one Al, and one Si atom. In the ninth O site, O is bonded in a 3-coordinate geometry to one Ca, one Al, and one Si atom. In the tenth O site, O is bonded in a distorted trigonal non-coplanar geometry to one Ca, one Al, and one Si atom. In the eleventh O site, O is bonded in a bent 120 degrees geometry to one Al and one Si atom. In the twelfth O site, O is bonded in a bent 120 degrees geometry to one Al and one Si atom. In the thirteenth O site, O is bonded in a 2-coordinate geometry to one Ca, one Al, and one Si atom. In the fourteenth O site, O is bonded in a distorted bent 120 degrees geometry to one Ca, one Al, and one Si atom. In the fifteenth O site, O is bonded in a distorted T-shaped geometry to one Ca, one Al, and one Si atom. In the sixteenth O site, O is bonded in a distorted T-shaped geometry to one Ca, one Al, and one Si atom. In the seventeenth O site, O is bonded in a water-like geometry to one Ca and one O atom. The O–O bond length is 1.23 Å. In the eighteenth O site, O is bonded in a distorted L-shaped geometry to one Ca and one O atom. The O–O bond length is 1.24 Å. In the nineteenth O site, O is bonded in a 1-coordinate geometry to one Ca and one O atom. In the twentieth O site, O is bonded in a distorted bent 150 degrees geometry to one Ca and one O atom. The O–O bond length is 1.23 Å. In the twenty-first O site, O is bonded in a bent 120 degrees geometry to one Ca and one O atom. The O–O bond length is 1.23 Å. In the twenty-second O site, O is bonded in a single-bond geometry to one O atom. In the twenty-third O site, O is bonded in a bent 120 degrees geometry to one Ca and one O atom. In the twenty-fourth O site, O is bonded in a bent 150 degrees geometry to one Ca and one O atom.

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2020-04-29. Materials Data on CaAl2(SiO6)2 by Materials Project. https://doi.org/10.17188/1718714

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