Materials Data on LaAl2Si5N9O by Materials Project

Abstract

LaAl2Si5N9O is Chalcostibite-derived structured and crystallizes in the monoclinic Pc space group. The structure is three-dimensional. there are two inequivalent La3+ sites. In the first La3+ site, La3+ is bonded in a 9-coordinate geometry to seven N3- and two O2- atoms. There are a spread of La–N bond distances ranging from 2.44–3.02 Å. There are one shorter (2.51 Å) and one longer (2.78 Å) La–O bond lengths. In the second La3+ site, La3+ is bonded in a 2-coordinate geometry to nine N3- atoms. There are a spread of La–N bond distances ranging from 2.33–3.01 Å. There are four inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to three N3- and one O2- atom to form AlN3O tetrahedra that share corners with three AlN4 tetrahedra and corners with five SiN4 tetrahedra. There are a spread of Al–N bond distances ranging from 1.79–1.91 Å. The Al–O bond length is 1.89 Å. In the second Al3+ site, Al3+ is bonded to four N3- atoms to form AlN4 tetrahedra that share a cornercorner with one AlN3O tetrahedra and corners with seven SiN4 tetrahedra. There are a spread of Al–N bond distances ranging from 1.84–1.95 Å. In the third Al3+ site, Al3+ is bonded to four N3- atoms to form AlN4 tetrahedra that share corners with two AlN3O tetrahedra and corners with six SiN4 tetrahedra. There are a spread of Al–N bond distances ranging from 1.88–1.98 Å. In the fourth Al3+ site, Al3+ is bonded to two N3- and two O2- atoms to form distorted AlN2O2 tetrahedra that share corners with two AlN3O tetrahedra and corners with five SiN2O2 tetrahedra. Both Al–N bond lengths are 1.90 Å. There is one shorter (1.78 Å) and one longer (1.79 Å) Al–O bond length. There are ten inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share corners with three AlN3O tetrahedra and corners with four SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.72–1.83 Å. In the second Si4+ site, Si4+ is bonded to two N3- and two O2- atoms to form SiN2O2 tetrahedra that share corners with three SiN4 tetrahedra and corners with four AlN3O tetrahedra. Both Si–N bond lengths are 1.71 Å. There is one shorter (1.66 Å) and one longer (1.73 Å) Si–O bond length. In the third Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share corners with two AlN3O tetrahedra and corners with five SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.70–1.84 Å. In the fourth Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share corners with two AlN4 tetrahedra and corners with six SiN2O2 tetrahedra. There are a spread of Si–N bond distances ranging from 1.73–1.80 Å. In the fifth Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share a cornercorner with one AlN4 tetrahedra and corners with six SiN2O2 tetrahedra. There are a spread of Si–N bond distances ranging from 1.75–1.80 Å. In the sixth Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share a cornercorner with one AlN4 tetrahedra and corners with six SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.69–1.85 Å. In the seventh Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share corners with two AlN4 tetrahedra and corners with six SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.71–1.82 Å. In the eighth Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share corners with two AlN4 tetrahedra and corners with five SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.73–1.80 Å. In the ninth Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share corners with two AlN3O tetrahedra and corners with five SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.72–1.82 Å. In the tenth Si4+ site, Si4+ is bonded to four N3- atoms to form SiN4 tetrahedra that share corners with four AlN4 tetrahedra and corners with four SiN4 tetrahedra. There are a spread of Si–N bond distances ranging from 1.73–1.83 Å. There are eighteen inequivalent N3- sites. In the first N3- site, N3- is bonded in a trigonal planar geometry to two Al3+ and one Si4+ atom. In the second N3- site, N3- is bonded in a trigonal non-coplanar geometry to one Al3+ and two Si4+ atoms. In the third N3- site, N3- is bonded in a trigonal planar geometry to one Al3+ and two Si4+ atoms. In the fourth N3- site, N3- is bonded in a trigonal planar geometry to three Si4+ atoms. In the fifth N3- site, N3- is bonded in a trigonal non-coplanar geometry to one Al3+ and two Si4+ atoms. In the sixth N3- site, N3- is bonded in a trigonal planar geometry to one Al3+ and two Si4+ atoms. In the seventh N3- site, N3- is bonded in a distorted T-shaped geometry to one La3+ and two Si4+ atoms. In the eighth N3- site, N3- is bonded in a distorted trigonal planar geometry to one La3+ and three Si4+ atoms. In the ninth N3- site, N3- is bonded in a trigonal planar geometry to three Si4+ atoms. In the tenth N3- site, N3- is bonded in a 2-coordinate geometry to two La3+ and two Si4+ atoms. In the eleventh N3- site, N3- is bonded in a distorted trigonal planar geometry to one La3+, one Al3+, and two Si4+ atoms. In the twelfth N3- site, N3- is bonded in a distorted trigonal non-coplanar geometry to two La3+, one Al3+, and two Si4+ atoms. In the thirteenth N3- site, N3- is bonded in a distorted trigonal planar geometry to two equivalent La3+ and three Si4+ atoms. In the fourteenth N3- site, N3- is bonded in a 3-coordinate geometry to two equivalent La3+, one Al3+, and two Si4+ atoms. In the fifteenth N3- site, N3- is bonded in a distorted trigonal non-coplanar geometry to two La3+, two Al3+, and one Si4+ atom. In the sixteenth N3- site, N3- is bonded in a 4-coordinate geometry to one La3+, two Al3+, and one Si4+ atom. In the seventeenth N3- site, N3- is bonded in a 2-coordinate geometry to two La3+ and two Si4+ atoms. In the eighteenth N3- site, N3- is bonded in a trigonal planar geometry to three Si4+ atoms. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one La3+, two Al3+, and one Si4+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one La3+, one Al3+, and one Si4+ atom.