Materials Data on CaAl2Si2(WO2)4 by Materials Project
WCaW3Al2Si2O8 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional and consists of four tungsten molecules and one CaW3Al2Si2O8 framework. In the CaW3Al2Si2O8 framework, there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.48 Å. In the second Ca2+ site, Ca2+ is bonded in a 3-coordinate geometry to three O2- atoms. There are two shorter (2.39 Å) and one longer (2.70 Å) Ca–O bond lengths. There are six inequivalent W2+ sites. In the first W2+ site, W2+ is bonded in a single-bond geometry to one O2- atom. The W–O bond length is 2.30 Å. In the second W2+ site, W2+ is bonded in a single-bond geometry to one O2- atom. The W–O bond length is 2.28 Å. In the third W2+ site, W2+ is bonded in a single-bond geometry to one O2- atom. The W–O bond length is 2.37 Å. In the fourth W2+ site, W2+ is bonded in a single-bond geometry to one O2- atom. The W–O bond length is 2.41 Å. In the fifth W2+ site, W2+ is bonded in a single-bond geometry to one O2- atom. The W–O bond length is 2.29 Å. In the sixth W2+ site, W2+ is bonded in a single-bond geometry to one O2- atom. The W–O bond length is 2.30 Å. There are four inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra. There is three shorter (1.78 Å) and one longer (1.79 Å) Al–O bond length. In the second Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.75–1.82 Å. In the third Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.77–1.79 Å. In the fourth Al3+ site, Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with four SiO4 tetrahedra. There are a spread of Al–O bond distances ranging from 1.74–1.82 Å. There are four inequivalent Si sites. In the first Si site, Si is bonded to four O2- 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 second Si site, Si is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.60–1.67 Å. In the third Si site, Si is bonded to four O2- atoms to form SiO4 tetrahedra that share corners with four AlO4 tetrahedra. There are a spread of Si–O bond distances ranging from 1.61–1.68 Å. In the fourth Si site, Si is bonded to four O2- 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 sixteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Al3+, and one Si atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one W2+, one Al3+, and one Si atom. In the third O2- site, O2- is bonded in a linear geometry to one Al3+ and one Si atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to one W2+, one Al3+, and one Si atom. In the fifth O2- site, O2- is bonded in a linear geometry to one Al3+ and one Si atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one Al3+ and one Si atom. In the seventh O2- site, O2- is bonded in a 3-coordinate geometry to one W2+, one Al3+, and one Si atom. In the eighth O2- site, O2- is bonded in a distorted trigonal planar geometry to one W2+, one Al3+, and one Si atom. In the ninth O2- site, O2- is bonded in a 2-coordinate geometry to one Ca2+, one Al3+, and one Si atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to one Ca2+, one Al3+, and one Si atom. In the eleventh O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Al3+, and one Si atom. In the twelfth O2- site, O2- is bonded in a bent 150 degrees geometry to one Al3+ and one Si atom. In the thirteenth O2- site, O2- is bonded in a 3-coordinate geometry to one W2+, one Al3+, and one Si atom. In the fourteenth O2- site, O2- is bonded in a 2-coordinate geometry to one W2+, one Al3+, and one Si atom. In the fifteenth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Ca2+, one Al3+, and one Si atom. In the sixteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Al3+, and one Si atom.