BaAl2O6 crystallizes in the orthorhombic Pna2_1 space group. Ba(1) is bonded in a 8-coordinate geometry to one O(2), one O(4), one O(5), one O(6), two equivalent O(1), and two equivalent O(3) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form corner-sharing AlO4 tetrahedra. In the second Al site, Al(2) is bonded to one O(1), one O(6), and two equivalent O(5) atoms to form corner-sharing AlO4 tetrahedra. There are six inequivalent O sites. In the first O site, O(6) is bonded in a distorted single-bond geometry to one Ba(1), one Al(2), and one O(4) atom. In the second O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(1), one Al(1), and one Al(2) atom. In the third O site, O(2) is bonded in a bent 150 degrees geometry to one Ba(1) and one Al(1) atom. In the fourth O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(1) and two equivalent Al(1) atoms. In the fifth O site, O(4) is bonded in a bent 120 degrees geometry to one Ba(1) and one O(6) atom. In the sixth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1) and two equivalent Al(2) atoms.
BaAl2O6 crystallizes in the orthorhombic Pna2_1 space group. Ba(1) is bonded in a 8-coordinate geometry to one O(2), one O(4), one O(5), one O(6), two equivalent O(1), and two equivalent O(3) atoms. The Ba(1)-O(2) bond length is 2.59 Å. The Ba(1)-O(4) bond length is 2.96 Å. The Ba(1)-O(5) bond length is 2.74 Å. The Ba(1)-O(6) bond length is 3.14 Å. There is one shorter (2.85 Å) and one longer (3.36 Å) Ba(1)-O(1) bond length. There is one shorter (2.85 Å) and one longer (2.92 Å) Ba(1)-O(3) bond length. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form corner-sharing AlO4 tetrahedra. The Al(1)-O(1) bond length is 1.77 Å. The Al(1)-O(2) bond length is 1.77 Å. Both Al(1)-O(3) bond lengths are 1.77 Å. In the second Al site, Al(2) is bonded to one O(1), one O(6), and two equivalent O(5) atoms to form corner-sharing AlO4 tetrahedra. The Al(2)-O(1) bond length is 1.73 Å. The Al(2)-O(6) bond length is 1.95 Å. There is one shorter (1.73 Å) and one longer (1.74 Å) Al(2)-O(5) bond length. There are six inequivalent O sites. In the first O site, O(6) is bonded in a distorted single-bond geometry to one Ba(1), one Al(2), and one O(4) atom. The O(6)-O(4) bond length is 1.33 Å. In the second O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(1), one Al(1), and one Al(2) atom. In the third O site, O(2) is bonded in a bent 150 degrees geometry to one Ba(1) and one Al(1) atom. In the fourth O site, O(3) is bonded in a distorted bent 150 degrees geometry to two equivalent Ba(1) and two equivalent Al(1) atoms. In the fifth O site, O(4) is bonded in a bent 120 degrees geometry to one Ba(1) and one O(6) atom. In the sixth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Ba(1) and two equivalent Al(2) atoms.