Ba5Si2N6 crystallizes in the orthorhombic P2_12_12_1 space group. There are five inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 6-coordinate geometry to one N(1), one N(2), one N(3), one N(4), one N(5), and one N(6) atom. In the second Ba site, Ba(2) is bonded in a 4-coordinate geometry to one N(1), one N(4), and two equivalent N(6) atoms. In the third Ba site, Ba(3) is bonded in a 5-coordinate geometry to one N(1), one N(2), one N(3), one N(4), and one N(6) atom. In the fourth Ba site, Ba(4) is bonded in a 6-coordinate geometry to one N(1), one N(5), two equivalent N(2), and two equivalent N(4) atoms. In the fifth Ba site, Ba(5) is bonded in a 7-coordinate geometry to one N(1), one N(2), one N(6), two equivalent N(3), and two equivalent N(5) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), one N(3), one N(5), and one N(6) atom to form edge-sharing SiN4 tetrahedra. In the second Si site, Si(2) is bonded to one N(2), one N(3), one N(4), and one N(5) atom to form edge-sharing SiN4 tetrahedra. There are six inequivalent N sites. In the first N site, N(2) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), one Ba(5), two equivalent Ba(4), and one Si(2) atom. In the second N site, N(3) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(3), two equivalent Ba(5), one Si(1), and one Si(2) atom. In the third N site, N(4) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), two equivalent Ba(4), and one Si(2) atom. In the fourth N site, N(5) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(4), two equivalent Ba(5), one Si(1), and one Si(2) atom. In the fifth N site, N(6) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), one Ba(5), two equivalent Ba(2), and one Si(1) atom. In the sixth N site, N(1) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Ba(5), and one Si(1) atom.
Ba5Si2N6 crystallizes in the orthorhombic P2_12_12_1 space group. There are five inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 6-coordinate geometry to one N(1), one N(2), one N(3), one N(4), one N(5), and one N(6) atom. The Ba(1)-N(1) bond length is 2.93 Å. The Ba(1)-N(2) bond length is 3.14 Å. The Ba(1)-N(3) bond length is 3.25 Å. The Ba(1)-N(4) bond length is 2.82 Å. The Ba(1)-N(5) bond length is 2.91 Å. The Ba(1)-N(6) bond length is 3.11 Å. In the second Ba site, Ba(2) is bonded in a 4-coordinate geometry to one N(1), one N(4), and two equivalent N(6) atoms. The Ba(2)-N(1) bond length is 2.71 Å. The Ba(2)-N(4) bond length is 2.73 Å. There is one shorter (2.64 Å) and one longer (2.76 Å) Ba(2)-N(6) bond length. In the third Ba site, Ba(3) is bonded in a 5-coordinate geometry to one N(1), one N(2), one N(3), one N(4), and one N(6) atom. The Ba(3)-N(1) bond length is 2.70 Å. The Ba(3)-N(2) bond length is 3.19 Å. The Ba(3)-N(3) bond length is 2.85 Å. The Ba(3)-N(4) bond length is 2.90 Å. The Ba(3)-N(6) bond length is 2.85 Å. In the fourth Ba site, Ba(4) is bonded in a 6-coordinate geometry to one N(1), one N(5), two equivalent N(2), and two equivalent N(4) atoms. The Ba(4)-N(1) bond length is 3.33 Å. The Ba(4)-N(5) bond length is 2.77 Å. There is one shorter (2.66 Å) and one longer (2.81 Å) Ba(4)-N(2) bond length. There is one shorter (2.85 Å) and one longer (3.06 Å) Ba(4)-N(4) bond length. In the fifth Ba site, Ba(5) is bonded in a 7-coordinate geometry to one N(1), one N(2), one N(6), two equivalent N(3), and two equivalent N(5) atoms. The Ba(5)-N(1) bond length is 2.91 Å. The Ba(5)-N(2) bond length is 2.74 Å. The Ba(5)-N(6) bond length is 2.73 Å. There is one shorter (2.77 Å) and one longer (3.21 Å) Ba(5)-N(3) bond length. There is one shorter (3.17 Å) and one longer (3.32 Å) Ba(5)-N(5) bond length. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), one N(3), one N(5), and one N(6) atom to form edge-sharing SiN4 tetrahedra. The Si(1)-N(1) bond length is 1.77 Å. The Si(1)-N(3) bond length is 1.85 Å. The Si(1)-N(5) bond length is 1.80 Å. The Si(1)-N(6) bond length is 1.77 Å. In the second Si site, Si(2) is bonded to one N(2), one N(3), one N(4), and one N(5) atom to form edge-sharing SiN4 tetrahedra. The Si(2)-N(2) bond length is 1.77 Å. The Si(2)-N(3) bond length is 1.84 Å. The Si(2)-N(4) bond length is 1.77 Å. The Si(2)-N(5) bond length is 1.84 Å. There are six inequivalent N sites. In the first N site, N(2) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), one Ba(5), two equivalent Ba(4), and one Si(2) atom. In the second N site, N(3) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(3), two equivalent Ba(5), one Si(1), and one Si(2) atom. In the third N site, N(4) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), two equivalent Ba(4), and one Si(2) atom. In the fourth N site, N(5) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(4), two equivalent Ba(5), one Si(1), and one Si(2) atom. In the fifth N site, N(6) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), one Ba(5), two equivalent Ba(2), and one Si(1) atom. In the sixth N site, N(1) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Ba(5), and one Si(1) atom.