Ba3SrSi8(NO)8 crystallizes in the triclinic P1 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one N(6), one O(1), two equivalent O(2), two equivalent O(7), and two equivalent O(8) atoms. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one N(5), one O(2), two equivalent O(1), two equivalent O(7), and two equivalent O(8) atoms. In the third Ba site, Ba(3) is bonded in a 8-coordinate geometry to one N(8), one O(3), two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms. Sr(1) is bonded in a 8-coordinate geometry to one N(7), one O(4), two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms. There are eight inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(2), one N(3), one N(5), and one O(1) atom to form corner-sharing SiN3O tetrahedra. In the second Si site, Si(2) is bonded to one N(1), one N(4), one N(6), and one O(2) atom to form corner-sharing SiN3O tetrahedra. In the third Si site, Si(3) is bonded to one N(1), one N(4), one N(7), and one O(3) atom to form corner-sharing SiN3O tetrahedra. In the fourth Si site, Si(4) is bonded to one N(2), one N(3), one N(8), and one O(4) atom to form corner-sharing SiN3O tetrahedra. In the fifth Si site, Si(5) is bonded to one N(3), one N(5), one N(8), and one O(5) atom to form corner-sharing SiN3O tetrahedra. In the sixth Si site, Si(6) is bonded to one N(4), one N(6), one N(7), and one O(6) atom to form corner-sharing SiN3O tetrahedra. In the seventh Si site, Si(7) is bonded to one N(1), one N(6), one N(7), and one O(7) atom to form corner-sharing SiN3O tetrahedra. In the eighth Si site, Si(8) is bonded to one N(2), one N(5), one N(8), and one O(8) atom to form corner-sharing SiN3O tetrahedra. There are eight inequivalent N sites. In the first N site, N(1) is bonded in a trigonal planar geometry to one Si(2), one Si(3), and one Si(7) atom. In the second N site, N(2) is bonded in a trigonal planar geometry to one Si(1), one Si(4), and one Si(8) atom. In the third N site, N(3) is bonded in a trigonal planar geometry to one Si(1), one Si(4), and one Si(5) atom. In the fourth N site, N(4) is bonded in a trigonal planar geometry to one Si(2), one Si(3), and one Si(6) atom. In the fifth N site, N(5) is bonded in a trigonal planar geometry to one Ba(2), one Si(1), one Si(5), and one Si(8) atom. In the sixth N site, N(6) is bonded in a trigonal planar geometry to one Ba(1), one Si(2), one Si(6), and one Si(7) atom. In the seventh N site, N(7) is bonded in a distorted trigonal planar geometry to one Sr(1), one Si(3), one Si(6), and one Si(7) atom. In the eighth N site, N(8) is bonded in a trigonal planar geometry to one Ba(3), one Si(4), one Si(5), and one Si(8) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Ba(3), two equivalent Sr(1), and one Si(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ba(3), one Sr(1), and one Si(4) atom. In the fifth O site, O(5) is bonded in a 1-coordinate geometry to two equivalent Ba(3), two equivalent Sr(1), and one Si(5) atom. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to two equivalent Ba(3), two equivalent Sr(1), and one Si(6) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to two equivalent Ba(1), two equivalent Ba(2), and one Si(7) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to two equivalent Ba(1), two equivalent Ba(2), and one Si(8) atom.
Ba3SrSi8(NO)8 crystallizes in the triclinic P1 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one N(6), one O(1), two equivalent O(2), two equivalent O(7), and two equivalent O(8) atoms. The Ba(1)-N(6) bond length is 3.15 Å. The Ba(1)-O(1) bond length is 2.73 Å. There is one shorter (2.69 Å) and one longer (2.70 Å) Ba(1)-O(2) bond length. There is one shorter (2.71 Å) and one longer (3.14 Å) Ba(1)-O(7) bond length. Both Ba(1)-O(8) bond lengths are 2.97 Å. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one N(5), one O(2), two equivalent O(1), two equivalent O(7), and two equivalent O(8) atoms. The Ba(2)-N(5) bond length is 3.17 Å. The Ba(2)-O(2) bond length is 2.75 Å. Both Ba(2)-O(1) bond lengths are 2.70 Å. There is one shorter (2.97 Å) and one longer (3.00 Å) Ba(2)-O(7) bond length. There is one shorter (2.72 Å) and one longer (3.12 Å) Ba(2)-O(8) bond length. In the third Ba site, Ba(3) is bonded in a 8-coordinate geometry to one N(8), one O(3), two equivalent O(4), two equivalent O(5), and two equivalent O(6) atoms. The Ba(3)-N(8) bond length is 3.18 Å. The Ba(3)-O(3) bond length is 2.69 Å. There is one shorter (2.72 Å) and one longer (2.73 Å) Ba(3)-O(4) bond length. There is one shorter (2.63 Å) and one longer (3.18 Å) Ba(3)-O(5) bond length. There is one shorter (2.97 Å) and one longer (2.99 Å) Ba(3)-O(6) bond length. Sr(1) is bonded in a 8-coordinate geometry to one N(7), one O(4), two equivalent O(3), two equivalent O(5), and two equivalent O(6) atoms. The Sr(1)-N(7) bond length is 3.04 Å. The Sr(1)-O(4) bond length is 2.53 Å. There is one shorter (2.63 Å) and one longer (2.67 Å) Sr(1)-O(3) bond length. There is one shorter (2.96 Å) and one longer (3.03 Å) Sr(1)-O(5) bond length. There is one shorter (2.54 Å) and one longer (3.25 Å) Sr(1)-O(6) bond length. There are eight inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(2), one N(3), one N(5), and one O(1) atom to form corner-sharing SiN3O tetrahedra. The Si(1)-N(2) bond length is 1.75 Å. The Si(1)-N(3) bond length is 1.74 Å. The Si(1)-N(5) bond length is 1.76 Å. The Si(1)-O(1) bond length is 1.63 Å. In the second Si site, Si(2) is bonded to one N(1), one N(4), one N(6), and one O(2) atom to form corner-sharing SiN3O tetrahedra. The Si(2)-N(1) bond length is 1.75 Å. The Si(2)-N(4) bond length is 1.75 Å. The Si(2)-N(6) bond length is 1.76 Å. The Si(2)-O(2) bond length is 1.63 Å. In the third Si site, Si(3) is bonded to one N(1), one N(4), one N(7), and one O(3) atom to form corner-sharing SiN3O tetrahedra. The Si(3)-N(1) bond length is 1.75 Å. The Si(3)-N(4) bond length is 1.76 Å. The Si(3)-N(7) bond length is 1.76 Å. The Si(3)-O(3) bond length is 1.63 Å. In the fourth Si site, Si(4) is bonded to one N(2), one N(3), one N(8), and one O(4) atom to form corner-sharing SiN3O tetrahedra. The Si(4)-N(2) bond length is 1.75 Å. The Si(4)-N(3) bond length is 1.75 Å. The Si(4)-N(8) bond length is 1.75 Å. The Si(4)-O(4) bond length is 1.63 Å. In the fifth Si site, Si(5) is bonded to one N(3), one N(5), one N(8), and one O(5) atom to form corner-sharing SiN3O tetrahedra. The Si(5)-N(3) bond length is 1.74 Å. The Si(5)-N(5) bond length is 1.77 Å. The Si(5)-N(8) bond length is 1.77 Å. The Si(5)-O(5) bond length is 1.63 Å. In the sixth Si site, Si(6) is bonded to one N(4), one N(6), one N(7), and one O(6) atom to form corner-sharing SiN3O tetrahedra. The Si(6)-N(4) bond length is 1.75 Å. The Si(6)-N(6) bond length is 1.76 Å. The Si(6)-N(7) bond length is 1.78 Å. The Si(6)-O(6) bond length is 1.63 Å. In the seventh Si site, Si(7) is bonded to one N(1), one N(6), one N(7), and one O(7) atom to form corner-sharing SiN3O tetrahedra. The Si(7)-N(1) bond length is 1.75 Å. The Si(7)-N(6) bond length is 1.77 Å. The Si(7)-N(7) bond length is 1.77 Å. The Si(7)-O(7) bond length is 1.63 Å. In the eighth Si site, Si(8) is bonded to one N(2), one N(5), one N(8), and one O(8) atom to form corner-sharing SiN3O tetrahedra. The Si(8)-N(2) bond length is 1.75 Å. The Si(8)-N(5) bond length is 1.77 Å. The Si(8)-N(8) bond length is 1.76 Å. The Si(8)-O(8) bond length is 1.63 Å. There are eight inequivalent N sites. In the first N site, N(1) is bonded in a trigonal planar geometry to one Si(2), one Si(3), and one Si(7) atom. In the second N site, N(2) is bonded in a trigonal planar geometry to one Si(1), one Si(4), and one Si(8) atom. In the third N site, N(3) is bonded in a trigonal planar geometry to one Si(1), one Si(4), and one Si(5) atom. In the fourth N site, N(4) is bonded in a trigonal planar geometry to one Si(2), one Si(3), and one Si(6) atom. In the fifth N site, N(5) is bonded in a trigonal planar geometry to one Ba(2), one Si(1), one Si(5), and one Si(8) atom. In the sixth N site, N(6) is bonded in a trigonal planar geometry to one Ba(1), one Si(2), one Si(6), and one Si(7) atom. In the seventh N site, N(7) is bonded in a distorted trigonal planar geometry to one Sr(1), one Si(3), one Si(6), and one Si(7) atom. In the eighth N site, N(8) is bonded in a trigonal planar geometry to one Ba(3), one Si(4), one Si(5), and one Si(8) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Ba(2), two equivalent Ba(1), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Ba(3), two equivalent Sr(1), and one Si(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ba(3), one Sr(1), and one Si(4) atom. In the fifth O site, O(5) is bonded in a 1-coordinate geometry to two equivalent Ba(3), two equivalent Sr(1), and one Si(5) atom. In the sixth O site, O(6) is bonded in a 1-coordinate geometry to two equivalent Ba(3), two equivalent Sr(1), and one Si(6) atom. In the seventh O site, O(7) is bonded in a distorted single-bond geometry to two equivalent Ba(1), two equivalent Ba(2), and one Si(7) atom. In the eighth O site, O(8) is bonded in a distorted single-bond geometry to two equivalent Ba(1), two equivalent Ba(2), and one Si(8) atom.