DOE OSTI2020
Sr(SrPr5Al6Si9(N2O)9)2 is Chalcostibite-derived structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional and consists of two strontium molecules and one SrPr5Al6Si9(N2O)9 framework. In the SrPr5Al6Si9(N2O)9 framework, Sr is bonded in a 5-coordinate geometry to five N and five O atoms. There are a spread of Sr–N bond distances ranging from 2.62–3.10 Å. There are a spread of Sr–O bond distances ranging from 2.65–3.09 Å. There are six inequivalent Pr sites. In the first Pr site, Pr is bonded in a 5-coordinate geometry to five N and five O atoms. There are a spread of Pr–N bond distances ranging from 2.55–3.09 Å. There are a spread of Pr–O bond distances ranging from 2.43–3.13 Å. In the second Pr site, Pr is bonded in a 5-coordinate geometry to five N and five O atoms. There are a spread of Pr–N bond distances ranging from 2.55–3.05 Å. There are a spread of Pr–O bond distances ranging from 2.41–3.10 Å. In the third Pr site, Pr is bonded in a 5-coordinate geometry to five N and five O atoms. There are a spread of Pr–N bond distances ranging from 2.53–3.11 Å. There are a spread of Pr–O bond distances ranging from 2.40–3.17 Å. In the fourth Pr site, Pr is bonded in a 2-coordinate geometry to five N and five O atoms. There are a spread of Pr–N bond distances ranging from 2.53–3.11 Å. There are a spread of Pr–O bond distances ranging from 2.42–3.18 Å. In the fifth Pr site, Pr is bonded in a 5-coordinate geometry to five N and five O atoms. There are a spread of Pr–N bond distances ranging from 2.55–3.07 Å. There are a spread of Pr–O bond distances ranging from 2.42–3.13 Å. In the sixth Pr site, Pr is bonded in a 5-coordinate geometry to five N and five O atoms. There are a spread of Pr–N bond distances ranging from 2.55–3.05 Å. There are a spread of Pr–O bond distances ranging from 2.47–3.10 Å. There are seven inequivalent Al sites. In the first Al site, Al is bonded to three N and one O atom to form AlN3O tetrahedra that share corners with two equivalent AlN3O tetrahedra and corners with five SiN4 tetrahedra. There is two shorter (1.83 Å) and one longer (1.88 Å) Al–N bond length. The Al–O bond length is 1.80 Å. In the second Al site, Al is bonded to three N and one O atom to form AlN3O tetrahedra that share corners with two equivalent AlN3O tetrahedra and corners with five SiN3O tetrahedra. There is two shorter (1.84 Å) and one longer (1.88 Å) Al–N bond length. The Al–O bond length is 1.81 Å. In the third Al site, Al is bonded to three N and one O atom to form AlN3O tetrahedra that share corners with two AlN3O tetrahedra and corners with five SiN4 tetrahedra. There are a spread of Al–N bond distances ranging from 1.83–1.89 Å. The Al–O bond length is 1.80 Å. In the fourth Al site, Al is bonded to three N and one O atom to form AlN3O tetrahedra that share corners with two AlN3O tetrahedra and corners with five SiN4 tetrahedra. There is two shorter (1.84 Å) and one longer (1.87 Å) Al–N bond length. The Al–O bond length is 1.79 Å. In the fifth Al site, Al is bonded to three N and one O atom to form AlN3O tetrahedra that share corners with two AlN3O tetrahedra and corners with five SiN4 tetrahedra. There are a spread of Al–N bond distances ranging from 1.83–1.88 Å. The Al–O bond length is 1.80 Å. In the sixth Al site, Al is bonded to three N and one O atom to form AlN3O tetrahedra that share corners with two AlN3O tetrahedra and corners with five SiN4 tetrahedra. There is two shorter (1.83 Å) and one longer (1.88 Å) Al–N bond length. The Al–O bond length is 1.80 Å. In the seventh Al site, Al is bonded to three N and one O atom to form AlN3O tetrahedra that share corners with two AlN3O tetrahedra and corners with five SiN3O tetrahedra. There is two shorter (1.83 Å) and one longer (1.89 Å) Al–N bond length. The Al–O bond length is 1.80 Å. There are eleven inequivalent Si sites. In the first Si site, Si is bonded to four N atoms to form SiN4 tetrahedra that share corners with two SiN3O tetrahedra and corners with four AlN3O tetrahedra. There are a spread of Si–N bond distances ranging from 1.72–1.74 Å. In the second Si site, Si is bonded to three N and one O atom to form SiN3O tetrahedra that share corners with three AlN3O tetrahedra and corners with three SiN4 tetrahedra. There is one shorter (1.74 Å) and two longer (1.75 Å) Si–N bond length. The Si–O bond length is 1.66 Å. In the third Si site, Si is bonded to three N and one O atom to form SiN3O tetrahedra that share corners with three AlN3O tetrahedra and corners with three SiN4 tetrahedra. There is one shorter (1.73 Å) and two longer (1.75 Å) Si–N bond length. The Si–O bond length is 1.67 Å. In the fourth Si site, Si is bonded to four N atoms to form SiN4 tetrahedra that share corners with two equivalent SiN3O tetrahedra and corners with four AlN3O tetrahedra. There is two shorter (1.72 Å) and two longer (1.74 Å) Si–N bond length. In the fifth Si site, Si is bonded to three N and one O atom to form SiN3O tetrahedra that share corners with three AlN3O tetrahedra and corners with three SiN3O tetrahedra. There is one shorter (1.73 Å) and two longer (1.75 Å) Si–N bond length. The Si–O bond length is 1.66 Å. In the sixth Si site, Si is bonded to three N and one O atom to form SiN3O tetrahedra that share corners with three AlN3O tetrahedra and corners with three SiN3O tetrahedra. There is one shorter (1.72 Å) and two longer (1.76 Å) Si–N bond length. The Si–O bond length is 1.65 Å. In the seventh Si site, Si is bonded to three N and one O atom to form SiN3O tetrahedra that share corners with three AlN3O tetrahedra and corners with three SiN3O tetrahedra. There are a spread of Si–N bond distances ranging from 1.73–1.76 Å. The Si–O bond length is 1.67 Å. In the eighth Si site, Si is bonded to three N and one O atom to form SiN3O tetrahedra that share corners with three AlN3O tetrahedra and corners with three SiN4 tetrahedra. There is two shorter (1.74 Å) and one longer (1.76 Å) Si–N bond length. The Si–O bond length is 1.66 Å. In the ninth Si site, Si is bonded to four N atoms to form SiN4 tetrahedra that share corners with two SiN3O tetrahedra and corners with four AlN3O tetrahedra. There are a spread of Si–N bond distances ranging from 1.72–1.74 Å. In the tenth Si site, Si is bonded to four N atoms to form SiN4 tetrahedra that share corners with two SiN3O tetrahedra and corners with four AlN3O tetrahedra. There are a spread of Si–N bond distances ranging from 1.72–1.74 Å. In the eleventh Si site, Si is bonded to three N and one O atom to form SiN3O tetrahedra that share corners with three AlN3O tetrahedra and corners with three SiN3O tetrahedra. There is one shorter (1.73 Å) and two longer (1.75 Å) Si–N bond length. The Si–O bond length is 1.66 Å. There are twenty-one inequivalent N sites. In the first N site, N is bonded in a 4-coordinate geometry to one Pr, one Al, and two Si atoms. In the second N site, N is bonded in a trigonal planar geometry to one Pr, two Al, and one Si atom. In the third N site, N is bonded in a 2-coordinate geometry to three Pr and two Si atoms. In the fourth N site, N is bonded in a 2-coordinate geometry to one Sr, two Pr, and two Si atoms. In the fifth N site, N is bonded in a 2-coordinate geometry to one Sr, two Pr, and two Si atoms. In the sixth N site, N is bonded to one Pr, one Al, and two Si atoms to form distorted NPrAlSi2 trigonal pyramids that share corners with two OPr4 tetrahedra and corners with two NPrAlSi2 trigonal pyramids. In the seventh N site, N is bonded in a trigonal planar geometry to one Sr, two Al, and one Si atom. In the eighth N site, N is bonded to one Pr, one Al, and two Si atoms to form distorted NPrAlSi2 tetrahedra that share a cornercorner with one NPrAlSi2 tetrahedra, corners with two OSrPr3 tetrahedra, and a cornercorner with one NSrAlSi2 trigonal pyramid. In the ninth N site, N is bonded in a 2-coordinate geometry to one Sr, two Pr, and two Si atoms. In the tenth N site, N is bonded in a trigonal planar geometry to one Pr, two Al, and one Si atom. In the eleventh N site, N is bonded in a trigonal planar geometry to one Pr, two Al, and one Si atom. In the twelfth N site, N is bonded to one Pr, one Al, and two Si atoms to form distorted NPrAlSi2 tetrahedra that share a cornercorner with one NPrAlSi2 tetrahedra, corners with two OPr4 tetrahedra, and a cornercorner with one NSrAlSi2 trigonal pyramid. In the thirteenth N site, N is bonded to one Sr, one Al, and two Si atoms to form distorted NSrAlSi2 trigonal pyramids that share corners with two NPrAlSi2 tetrahedra and corners with two OSrPr3 tetrahedra. In the fourteenth N site, N is bonded in a trigonal planar geometry to one Pr, two Al, and one Si atom. In the fifteenth N site, N is bonded in a 2-coordinate geometry to three Pr and two Si atoms. In the sixteenth N site, N is bonded in a 2-coordinate geometry to three Pr and two Si atoms. In the seventeenth N site, N is bonded in a 2-coordinate geometry to three Pr and two Si atoms. In the eighteenth N site, N is bonded to one Pr, one Al, and two equivalent Si atoms to form distorted NPrAlSi2 trigonal pyramids that share corners with two equivalent OSrPr3 tetrahedra and corners with two equivalent NPrAlSi2 trigonal pyramids. In the nineteenth N site, N is bonded to one Pr, one Al, and two equivalent Si atoms to form distorted NPrAlSi2 trigonal pyramids that share corners with two equivalent OPr4 tetrahedra. In the twentieth N site, N is bonded in a trigonal planar geometry to one Pr, two equivalent Al, and one Si atom. In the twenty-first N site, N is bonded in a trigonal planar geometry to one Pr, two equivalent Al, and one Si atom. There are ten inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to three Pr, one Al, and one Si atom. In the second O site, O is bonded in a 2-coordinate geometry to three Pr, one Al, and one Si atom. In the third O site, O is bonded in a 2-coordinate geometry to one Sr, two Pr, one Al, and one Si atom. In the fourth O site, O is bonded to four Pr atoms to form distorted OPr4 tetrahedra that share corners with two NPrAlSi2 tetrahedra, corners with four OPr4 tetrahedra, and corners with two NPrAlSi2 trigonal pyramids. In the fifth O site, O is bonded to one Sr and three Pr atoms to form distorted OSrPr3 tetrahedra that share a cornercorner with one NPrAlSi2 tetrahedra, corners with four OPr4 tetrahedra, and corners with two NSrAlSi2 trigonal pyramids. In the sixth O site, O is bonded in a 2-coordinate geometry to one Sr, two Pr, one Al, and one Si atom. In the seventh O site, O is bonded in a 2-coordinate geometry to three Pr, one Al, and one Si atom. In the eighth O site, O is bonded in a 2-coordinate geometry to one Sr, two Pr, one Al, and one Si atom. In the ninth O site, O is bonded in a 2-coordinate geometry to three Pr, one Al, and one Si atom. In the tenth O site, O is bonded to one Sr and three Pr atoms to form OSrPr3 tetrahedra that share a cornercorner with one NPrAlSi2 tetrahedra, corners with four OPr4 tetrahedra, and corners with two NSrAlSi2 trigonal pyramids.