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DOE OSTI · 1663050

Materials Data on Ca6Al3(Si4N9)2 by Materials Project

Abstract

Ca6Al3(Si4N9)2 is Chalcostibite-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 6-coordinate geometry to six N+2.94- atoms. There are a spread of Ca–N bond distances ranging from 2.30–2.98 Å. In the second Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to five N+2.94- atoms. There are a spread of Ca–N bond distances ranging from 2.35–2.62 Å. In the third Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven N+2.94- atoms. There are a spread of Ca–N bond distances ranging from 2.27–2.87 Å. In the fourth Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to five N+2.94- atoms. There are a spread of Ca–N bond distances ranging from 2.39–2.71 Å. In the fifth Ca2+ site, Ca2+ is bonded in a 5-coordinate geometry to five N+2.94- atoms. There are a spread of Ca–N bond distances ranging from 2.54–2.59 Å. In the sixth Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to six N+2.94- atoms. There are a spread of Ca–N bond distances ranging from 2.41–2.95 Å. There are three inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to four N+2.94- atoms to form AlN4 tetrahedra that share corners with two AlN4 tetrahedra and corners with five SiN4 tetrahedra. There are a spread of Al–N bond distances ranging from 1.85–1.92 Å. In the second Al3+ site, Al3+ is bonded to four N+2.94- atoms to form AlN4 tetrahedra that share a cornercorner with one AlN4 tetrahedra and corners with six SiN4 tetrahedra. There are a spread of Al–N bond distances ranging from 1.85–1.90 Å. In the third Al3+ site, Al3+ is bonded to four N+2.94- atoms to form AlN4 tetrahedra that share a cornercorner with one AlN4 tetrahedra and corners with six SiN4 tetrahedra. There are a spread of Al–N bond distances ranging from 1.86–1.91 Å. There are eight inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four N+2.94- atoms to form SiN4 tetrahedra that share a cornercorner with one AlN4 tetrahedra and corners with five SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.70–1.83 Å. In the second Si4+ site, Si4+ is bonded to four N+2.94- atoms to form SiN4 tetrahedra that share a cornercorner with one AlN4 tetrahedra and corners with five SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.70–1.82 Å. In the third Si4+ site, Si4+ is bonded to four N+2.94- atoms to form SiN4 tetrahedra that share corners with two AlN4 tetrahedra and corners with four SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.69–1.84 Å. In the fourth Si4+ site, Si4+ is bonded to four N+2.94- atoms to form SiN4 tetrahedra that share corners with three AlN4 tetrahedra and corners with four SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.73–1.81 Å. In the fifth Si4+ site, Si4+ is bonded to four N+2.94- atoms to form SiN4 tetrahedra that share corners with two AlN4 tetrahedra and corners with four SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.71–1.80 Å. In the sixth Si4+ site, Si4+ is bonded to four N+2.94- atoms to form SiN4 tetrahedra that share corners with two AlN4 tetrahedra and corners with four SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.69–1.83 Å. In the seventh Si4+ site, Si4+ is bonded to four N+2.94- atoms to form SiN4 tetrahedra that share corners with three AlN4 tetrahedra and corners with three SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.71–1.80 Å. In the eighth Si4+ site, Si4+ is bonded to four N+2.94- atoms to form SiN4 tetrahedra that share corners with three AlN4 tetrahedra and corners with three SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.71–1.82 Å. There are eighteen inequivalent N+2.94- sites. In the first N+2.94- site, N+2.94- is bonded in a 2-coordinate geometry to three Ca2+, one Al3+, and one Si4+ atom. In the second N+2.94- site, N+2.94- is bonded in a 6-coordinate geometry to four Ca2+ and two Si4+ atoms. In the third N+2.94- site, N+2.94- is bonded in a 2-coordinate geometry to three Ca2+ and two Si4+ atoms. In the fourth N+2.94- site, N+2.94- is bonded in a 2-coordinate geometry to four Ca2+, one Al3+, and one Si4+ atom. In the fifth N+2.94- site, N+2.94- is bonded in a distorted see-saw-like geometry to three Ca2+ and one Si4+ atom. In the sixth N+2.94- site, N+2.94- is bonded to three Ca2+, one Al3+, and one Si4+ atom to form distorted NCa3AlSi trigonal bipyramids that share a cornercorner with one NCaAl2Si tetrahedra, corners with five NCaAl2Si trigonal pyramids, and edges with two NCaAlSi2 trigonal pyramids. In the seventh N+2.94- site, N+2.94- is bonded in a 4-coordinate geometry to two Ca2+ and two Si4+ atoms. In the eighth N+2.94- site, N+2.94- is bonded to one Ca2+, two Al3+, and one Si4+ atom to form distorted NCaAl2Si tetrahedra that share a cornercorner with one NCa3AlSi trigonal bipyramid and corners with six NCaAlSi2 trigonal pyramids. In the ninth N+2.94- site, N+2.94- is bonded to one Ca2+, one Al3+, and two Si4+ atoms to form NCaAlSi2 trigonal pyramids that share a cornercorner with one NCa3AlSi trigonal bipyramid and corners with five NCaAl2Si trigonal pyramids. In the tenth N+2.94- site, N+2.94- is bonded to one Ca2+, one Al3+, and two Si4+ atoms to form distorted NCaAlSi2 trigonal pyramids that share a cornercorner with one NCaAl2Si tetrahedra, a cornercorner with one NCa3AlSi trigonal bipyramid, and corners with four NCaAl2Si trigonal pyramids. In the eleventh N+2.94- site, N+2.94- is bonded in a distorted trigonal non-coplanar geometry to one Ca2+ and two Si4+ atoms. In the twelfth N+2.94- site, N+2.94- is bonded to one Ca2+, one Al3+, and two Si4+ atoms to form NCaAlSi2 trigonal pyramids that share a cornercorner with one NCaAl2Si tetrahedra, a cornercorner with one NCa3AlSi trigonal bipyramid, and corners with five NCaAlSi2 trigonal pyramids. In the thirteenth N+2.94- site, N+2.94- is bonded to one Ca2+, one Al3+, and two Si4+ atoms to form distorted NCaAlSi2 trigonal pyramids that share a cornercorner with one NCaAl2Si tetrahedra, corners with four NCaAlSi2 trigonal pyramids, and an edgeedge with one NCa3AlSi trigonal bipyramid. In the fourteenth N+2.94- site, N+2.94- is bonded to one Ca2+ and three Si4+ atoms to form distorted NCaSi3 trigonal pyramids that share a cornercorner with one NCa3AlSi trigonal bipyramid and corners with four NCaAlSi2 trigonal pyramids. In the fifteenth N+2.94- site, N+2.94- is bonded to one Ca2+ and three Si4+ atoms to form distorted NCaSi3 trigonal pyramids that share a cornercorner with one NCaAl2Si tetrahedra and corners with four NCaAlSi2 trigonal pyramids. In the sixteenth N+2.94- site, N+2.94- is bonded to one Ca2+, one Al3+, and two Si4+ atoms to form distorted NCaAlSi2 trigonal pyramids that share a cornercorner with one NCaAl2Si tetrahedra, corners with four NCaAlSi2 trigonal pyramids, and an edgeedge with one NCa3AlSi trigonal bipyramid. In the seventeenth N+2.94- site, N+2.94- is bonded to one Ca2+, two Al3+, and one Si4+ atom to form distorted NCaAl2Si trigonal pyramids that share a cornercorner with one NCaAl2Si tetrahedra, a cornercorner with one NCa3AlSi trigonal bipyramid, and corners with six NCaAlSi2 trigonal pyramids. In the eighteenth N+2.94- site, N+2.94- is bonded in a 3-coordinate geometry to two Ca2+ and two Si4+ atoms.

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2020-07-15. Materials Data on Ca6Al3(Si4N9)2 by Materials Project. https://doi.org/10.17188/1663050

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