Ba3Al3N5 crystallizes in the triclinic P-1 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 6-coordinate geometry to one N(1), one N(3), one N(4), one N(5), and two equivalent N(2) atoms. In the second Ba site, Ba(2) is bonded in a 5-coordinate geometry to one N(1), one N(3), one N(4), and two equivalent N(5) atoms. In the third Ba site, Ba(3) is bonded in a 5-coordinate geometry to one N(1), one N(2), one N(4), and two equivalent N(3) atoms. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one N(1), one N(5), and two equivalent N(3) atoms to form a mixture of edge and corner-sharing AlN4 tetrahedra. In the second Al site, Al(2) is bonded to one N(1), one N(2), and two equivalent N(4) atoms to form a mixture of distorted edge and corner-sharing AlN4 tetrahedra. In the third Al site, Al(3) is bonded to one N(1), one N(2), one N(4), and one N(5) atom to form a mixture of edge and corner-sharing AlN4 tetrahedra. There are five inequivalent N sites. In the first N site, N(1) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Al(1), one Al(2), and one Al(3) atom. In the second N site, N(2) is bonded in a 2-coordinate geometry to one Ba(3), two equivalent Ba(1), one Al(2), and one Al(3) atom. In the third N site, N(3) is bonded to one Ba(1), one Ba(2), two equivalent Ba(3), and two equivalent Al(1) atoms to form distorted edge-sharing NBa4Al2 octahedra. In the fourth N site, N(4) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Al(3), and two equivalent Al(2) atoms. In the fifth N site, N(5) is bonded in a 2-coordinate geometry to one Ba(1), two equivalent Ba(2), one Al(1), and one Al(3) atom.
Ba3Al3N5 crystallizes in the triclinic P-1 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 6-coordinate geometry to one N(1), one N(3), one N(4), one N(5), and two equivalent N(2) atoms. The Ba(1)-N(1) bond length is 3.32 Å. The Ba(1)-N(3) bond length is 2.68 Å. The Ba(1)-N(4) bond length is 2.86 Å. The Ba(1)-N(5) bond length is 3.21 Å. There is one shorter (2.66 Å) and one longer (3.00 Å) Ba(1)-N(2) bond length. In the second Ba site, Ba(2) is bonded in a 5-coordinate geometry to one N(1), one N(3), one N(4), and two equivalent N(5) atoms. The Ba(2)-N(1) bond length is 2.84 Å. The Ba(2)-N(3) bond length is 2.88 Å. The Ba(2)-N(4) bond length is 3.03 Å. There is one shorter (2.82 Å) and one longer (2.84 Å) Ba(2)-N(5) 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(4), and two equivalent N(3) atoms. The Ba(3)-N(1) bond length is 2.79 Å. The Ba(3)-N(2) bond length is 2.72 Å. The Ba(3)-N(4) bond length is 2.91 Å. There is one shorter (2.67 Å) and one longer (2.75 Å) Ba(3)-N(3) bond length. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to one N(1), one N(5), and two equivalent N(3) atoms to form a mixture of edge and corner-sharing AlN4 tetrahedra. The Al(1)-N(1) bond length is 1.98 Å. The Al(1)-N(5) bond length is 1.93 Å. There is one shorter (1.93 Å) and one longer (1.94 Å) Al(1)-N(3) bond length. In the second Al site, Al(2) is bonded to one N(1), one N(2), and two equivalent N(4) atoms to form a mixture of distorted edge and corner-sharing AlN4 tetrahedra. The Al(2)-N(1) bond length is 1.95 Å. The Al(2)-N(2) bond length is 1.91 Å. There is one shorter (1.95 Å) and one longer (2.02 Å) Al(2)-N(4) bond length. In the third Al site, Al(3) is bonded to one N(1), one N(2), one N(4), and one N(5) atom to form a mixture of edge and corner-sharing AlN4 tetrahedra. The Al(3)-N(1) bond length is 2.02 Å. The Al(3)-N(2) bond length is 1.93 Å. The Al(3)-N(4) bond length is 2.04 Å. The Al(3)-N(5) bond length is 1.91 Å. There are five inequivalent N sites. In the first N site, N(1) is bonded in a 3-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Al(1), one Al(2), and one Al(3) atom. In the second N site, N(2) is bonded in a 2-coordinate geometry to one Ba(3), two equivalent Ba(1), one Al(2), and one Al(3) atom. In the third N site, N(3) is bonded to one Ba(1), one Ba(2), two equivalent Ba(3), and two equivalent Al(1) atoms to form distorted edge-sharing NBa4Al2 octahedra. In the fourth N site, N(4) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Al(3), and two equivalent Al(2) atoms. In the fifth N site, N(5) is bonded in a 2-coordinate geometry to one Ba(1), two equivalent Ba(2), one Al(1), and one Al(3) atom.