Ba4OBr6 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one O(1), three equivalent Br(1), and four equivalent Br(2) atoms. In the second Ba site, Ba(2) is bonded in a distorted single-bond geometry to one O(1), three equivalent Br(1), and six equivalent Br(2) atoms. O(1) is bonded to one Ba(2) and three equivalent Ba(1) atoms to form OBa4 tetrahedra that share corners with six equivalent Br(1)Ba4 tetrahedra and edges with three equivalent Br(1)Ba4 tetrahedra. There are two inequivalent Br sites. In the first Br site, Br(1) is bonded to one Ba(2) and three equivalent Ba(1) atoms to form distorted BrBa4 tetrahedra that share corners with two equivalent O(1)Ba4 tetrahedra, corners with eight equivalent Br(1)Ba4 tetrahedra, and  an edgeedge with one O(1)Ba4 tetrahedra. In the second Br site, Br(2) is bonded in a 6-coordinate geometry to two equivalent Ba(2) and four equivalent Ba(1) atoms.
Ba4OBr6 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one O(1), three equivalent Br(1), and four equivalent Br(2) atoms. The Ba(1)-O(1) bond length is 2.56 Å. There is one shorter (3.30 Å) and two longer (3.33 Å) Ba(1)-Br(1) bond lengths. There are two shorter (3.38 Å) and two longer (3.57 Å) Ba(1)-Br(2) bond lengths. In the second Ba site, Ba(2) is bonded in a distorted single-bond geometry to one O(1), three equivalent Br(1), and six equivalent Br(2) atoms. The Ba(2)-O(1) bond length is 2.55 Å. All Ba(2)-Br(1) bond lengths are 3.46 Å. There are three shorter (3.38 Å) and three longer (3.95 Å) Ba(2)-Br(2) bond lengths. O(1) is bonded to one Ba(2) and three equivalent Ba(1) atoms to form OBa4 tetrahedra that share corners with six equivalent Br(1)Ba4 tetrahedra and edges with three equivalent Br(1)Ba4 tetrahedra. There are two inequivalent Br sites. In the first Br site, Br(1) is bonded to one Ba(2) and three equivalent Ba(1) atoms to form distorted BrBa4 tetrahedra that share corners with two equivalent O(1)Ba4 tetrahedra, corners with eight equivalent Br(1)Ba4 tetrahedra, and  an edgeedge with one O(1)Ba4 tetrahedra. In the second Br site, Br(2) is bonded in a 6-coordinate geometry to two equivalent Ba(2) and four equivalent Ba(1) atoms.