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 7-coordinate geometry to seven O atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.99 Å. In the second Ca site, Ca is bonded in a 7-coordinate geometry to seven O atoms. There are a spread of Ca–O bond distances ranging from 2.36–2.93 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 1.71–1.91 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 1.74–1.77 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 1.72–1.79 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 1.74–1.77 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 1.62–1.67 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 1.62–1.67 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 1.58–1.75 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 1.62–1.66 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 3-coordinate geometry to one Ca, one Al, and one Si atom. In the eleventh O site, O is bonded in a 3-coordinate geometry to one Al, one Si, and one O atom. The O–O bond length is 1.44 Å. 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 3-coordinate geometry to one Ca, one Al, and one Si atom. In the fourteenth O site, O is bonded in a 2-coordinate geometry to one Ca, one Al, and one Si atom. In the fifteenth O site, O is bonded in a 3-coordinate geometry to one Ca, one Al, and one Si atom. In the sixteenth O site, O is bonded in a 3-coordinate geometry to one Ca, one Al, and one Si atom. In the seventeenth O site, O is bonded in an L-shaped 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 single-bond geometry to one O atom. The O–O bond length is 1.24 Å. In the nineteenth O site, O is bonded in a water-like geometry to one Ca and one O atom. In the twentieth O site, O is bonded in a single-bond geometry to one Ca atom. In the twenty-first O site, O is bonded in a distorted water-like 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.