BaAlSi5O2N7 crystallizes in the monoclinic Pc space group. Ba(1) is bonded in a 10-coordinate geometry to one N(2), one N(4), one N(5), two equivalent N(6), two equivalent N(7), one O(1), and two equivalent O(2) atoms. Al(1) is bonded in a 5-coordinate geometry to one N(3), one N(5), one N(6), one N(7), and one O(1) atom. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded in a distorted trigonal non-coplanar geometry to one N(1), one N(6), and one O(1) atom. In the second Si site, Si(2) is bonded in a distorted trigonal non-coplanar geometry to one N(1), one N(6), and one O(2) atom. In the third Si site, Si(3) is bonded in a distorted trigonal non-coplanar geometry to one N(2), one N(4), and one O(2) atom. In the fourth Si site, Si(4) is bonded in a tetrahedral geometry to one N(2), one N(4), one N(5), and one N(7) atom. In the fifth Si site, Si(5) is bonded in a distorted see-saw-like geometry to one N(3), one N(4), one N(5), and one O(1) atom. There are seven inequivalent N sites. In the first N site, N(1) is bonded in a 3-coordinate geometry to one Si(1), one Si(2), and one N(2) atom. In the second N site, N(2) is bonded in a 2-coordinate geometry to one Ba(1), one Si(3), one Si(4), and one N(1) atom. In the third N site, N(3) is bonded in a 3-coordinate geometry to one Al(1), one Si(5), and one N(7) atom. In the fourth N site, N(4) is bonded in a 4-coordinate geometry to one Ba(1), one Si(3), one Si(4), and one Si(5) atom. In the fifth N site, N(5) is bonded in a distorted rectangular see-saw-like geometry to one Ba(1), one Al(1), one Si(4), and one Si(5) atom. In the sixth N site, N(6) is bonded in a distorted trigonal planar geometry to two equivalent Ba(1), one Al(1), one Si(1), and one Si(2) atom. In the seventh N site, N(7) is bonded in a 1-coordinate geometry to two equivalent Ba(1), one Al(1), one Si(4), and one N(3) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), one Al(1), one Si(1), and one Si(5) atom. In the second O site, O(2) is bonded in a distorted water-like geometry to two equivalent Ba(1), one Si(2), and one Si(3) atom.
BaAlSi5O2N7 crystallizes in the monoclinic Pc space group. Ba(1) is bonded in a 10-coordinate geometry to one N(2), one N(4), one N(5), two equivalent N(6), two equivalent N(7), one O(1), and two equivalent O(2) atoms. The Ba(1)-N(2) bond length is 2.85 Å. The Ba(1)-N(4) bond length is 2.73 Å. The Ba(1)-N(5) bond length is 2.85 Å. There is one shorter (3.37 Å) and one longer (3.40 Å) Ba(1)-N(6) bond length. There is one shorter (2.93 Å) and one longer (3.37 Å) Ba(1)-N(7) bond length. The Ba(1)-O(1) bond length is 3.37 Å. There is one shorter (2.75 Å) and one longer (3.09 Å) Ba(1)-O(2) bond length. Al(1) is bonded in a 5-coordinate geometry to one N(3), one N(5), one N(6), one N(7), and one O(1) atom. The Al(1)-N(3) bond length is 1.81 Å. The Al(1)-N(5) bond length is 1.95 Å. The Al(1)-N(6) bond length is 2.04 Å. The Al(1)-N(7) bond length is 2.06 Å. The Al(1)-O(1) bond length is 1.93 Å. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded in a distorted trigonal non-coplanar geometry to one N(1), one N(6), and one O(1) atom. The Si(1)-N(1) bond length is 1.78 Å. The Si(1)-N(6) bond length is 1.77 Å. The Si(1)-O(1) bond length is 1.75 Å. In the second Si site, Si(2) is bonded in a distorted trigonal non-coplanar geometry to one N(1), one N(6), and one O(2) atom. The Si(2)-N(1) bond length is 1.81 Å. The Si(2)-N(6) bond length is 1.73 Å. The Si(2)-O(2) bond length is 1.70 Å. In the third Si site, Si(3) is bonded in a distorted trigonal non-coplanar geometry to one N(2), one N(4), and one O(2) atom. The Si(3)-N(2) bond length is 1.79 Å. The Si(3)-N(4) bond length is 1.70 Å. The Si(3)-O(2) bond length is 1.70 Å. In the fourth Si site, Si(4) is bonded in a tetrahedral geometry to one N(2), one N(4), one N(5), and one N(7) atom. The Si(4)-N(2) bond length is 1.79 Å. The Si(4)-N(4) bond length is 1.74 Å. The Si(4)-N(5) bond length is 1.78 Å. The Si(4)-N(7) bond length is 1.74 Å. In the fifth Si site, Si(5) is bonded in a distorted see-saw-like geometry to one N(3), one N(4), one N(5), and one O(1) atom. The Si(5)-N(3) bond length is 1.74 Å. The Si(5)-N(4) bond length is 1.88 Å. The Si(5)-N(5) bond length is 1.83 Å. The Si(5)-O(1) bond length is 2.00 Å. There are seven inequivalent N sites. In the first N site, N(1) is bonded in a 3-coordinate geometry to one Si(1), one Si(2), and one N(2) atom. The N(1)-N(2) bond length is 1.54 Å. In the second N site, N(2) is bonded in a 2-coordinate geometry to one Ba(1), one Si(3), one Si(4), and one N(1) atom. In the third N site, N(3) is bonded in a 3-coordinate geometry to one Al(1), one Si(5), and one N(7) atom. The N(3)-N(7) bond length is 1.54 Å. In the fourth N site, N(4) is bonded in a 4-coordinate geometry to one Ba(1), one Si(3), one Si(4), and one Si(5) atom. In the fifth N site, N(5) is bonded in a distorted rectangular see-saw-like geometry to one Ba(1), one Al(1), one Si(4), and one Si(5) atom. In the sixth N site, N(6) is bonded in a distorted trigonal planar geometry to two equivalent Ba(1), one Al(1), one Si(1), and one Si(2) atom. In the seventh N site, N(7) is bonded in a 1-coordinate geometry to two equivalent Ba(1), one Al(1), one Si(4), and one N(3) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Ba(1), one Al(1), one Si(1), and one Si(5) atom. In the second O site, O(2) is bonded in a distorted water-like geometry to two equivalent Ba(1), one Si(2), and one Si(3) atom.