Ba2Tm2Al3Si5N11O3 crystallizes in the trigonal P3m1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted pentagonal pyramidal geometry to three equivalent N(1) and three equivalent N(3) atoms. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to three equivalent N(2) and three equivalent O(1) atoms. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a distorted T-shaped geometry to three equivalent O(1) atoms. In the second Tm site, Tm(2) is bonded in a 6-coordinate geometry to three equivalent N(2) and three equivalent N(3) atoms. Al(1) is bonded in a distorted trigonal planar geometry to one N(4) and two equivalent N(3) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 3-coordinate geometry to three equivalent Si(3) atoms. In the second Si site, Si(2) is bonded in a single-bond geometry to one N(5) atom. In the third Si site, Si(3) is bonded in a water-like geometry to one Si(1) and two equivalent N(1) atoms. There are five inequivalent N sites. In the first N site, N(1) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent Si(3), and one O(1) atom. In the second N site, N(2) is bonded in a 4-coordinate geometry to one Ba(2), one Tm(2), and two equivalent N(2) atoms. In the third N site, N(3) is bonded to one Ba(1), one Tm(2), and two equivalent Al(1) atoms to form distorted NBaTmAl2 trigonal pyramids that share corners with two equivalent N(4)Al3N tetrahedra, corners with two equivalent N(3)BaTmAl2 trigonal pyramids, and edges with two equivalent N(3)BaTmAl2 trigonal pyramids. In the fourth N site, N(4) is bonded to three equivalent Al(1) and one N(5) atom to form corner-sharing NAl3N tetrahedra. In the fifth N site, N(5) is bonded in a linear geometry to one Si(2) and one N(4) atom. O(1) is bonded in a 3-coordinate geometry to one Ba(2), one Tm(1), and one N(1) atom.
Ba2Tm2Al3Si5N11O3 crystallizes in the trigonal P3m1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted pentagonal pyramidal geometry to three equivalent N(1) and three equivalent N(3) atoms. All Ba(1)-N(1) bond lengths are 2.77 Å. All Ba(1)-N(3) bond lengths are 2.68 Å. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to three equivalent N(2) and three equivalent O(1) atoms. All Ba(2)-N(2) bond lengths are 2.50 Å. All Ba(2)-O(1) bond lengths are 2.54 Å. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a distorted T-shaped geometry to three equivalent O(1) atoms. All Tm(1)-O(1) bond lengths are 2.00 Å. In the second Tm site, Tm(2) is bonded in a 6-coordinate geometry to three equivalent N(2) and three equivalent N(3) atoms. All Tm(2)-N(2) bond lengths are 2.23 Å. All Tm(2)-N(3) bond lengths are 2.23 Å. Al(1) is bonded in a distorted trigonal planar geometry to one N(4) and two equivalent N(3) atoms. The Al(1)-N(4) bond length is 2.22 Å. Both Al(1)-N(3) bond lengths are 1.87 Å. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 3-coordinate geometry to three equivalent Si(3) atoms. All Si(1)-Si(3) bond lengths are 2.53 Å. In the second Si site, Si(2) is bonded in a single-bond geometry to one N(5) atom. The Si(2)-N(5) bond length is 1.66 Å. In the third Si site, Si(3) is bonded in a water-like geometry to one Si(1) and two equivalent N(1) atoms. Both Si(3)-N(1) bond lengths are 1.85 Å. There are five inequivalent N sites. In the first N site, N(1) is bonded in a 4-coordinate geometry to one Ba(1), two equivalent Si(3), and one O(1) atom. The N(1)-O(1) bond length is 1.46 Å. In the second N site, N(2) is bonded in a 4-coordinate geometry to one Ba(2), one Tm(2), and two equivalent N(2) atoms. Both N(2)-N(2) bond lengths are 1.46 Å. In the third N site, N(3) is bonded to one Ba(1), one Tm(2), and two equivalent Al(1) atoms to form distorted NBaTmAl2 trigonal pyramids that share corners with two equivalent N(4)Al3N tetrahedra, corners with two equivalent N(3)BaTmAl2 trigonal pyramids, and edges with two equivalent N(3)BaTmAl2 trigonal pyramids. In the fourth N site, N(4) is bonded to three equivalent Al(1) and one N(5) atom to form corner-sharing NAl3N tetrahedra. The N(4)-N(5) bond length is 1.46 Å. In the fifth N site, N(5) is bonded in a linear geometry to one Si(2) and one N(4) atom. O(1) is bonded in a 3-coordinate geometry to one Ba(2), one Tm(1), and one N(1) atom.