Rb4OBr2 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 6-coordinate geometry to one O(1) and five equivalent Br(1) atoms. In the second Rb site, Rb(2) is bonded in a distorted linear geometry to two equivalent O(1) and four equivalent Br(1) atoms. O(1) is bonded to two equivalent Rb(1) and four equivalent Rb(2) atoms to form corner-sharing ORb6 octahedra. The corner-sharing octahedra are not tilted. Br(1) is bonded in a 9-coordinate geometry to four equivalent Rb(2) and five equivalent Rb(1) atoms.
Rb4OBr2 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 6-coordinate geometry to one O(1) and five equivalent Br(1) atoms. The Rb(1)-O(1) bond length is 2.68 Å. There is one shorter (3.51 Å) and four longer (3.85 Å) Rb(1)-Br(1) bond lengths. In the second Rb site, Rb(2) is bonded in a distorted linear geometry to two equivalent O(1) and four equivalent Br(1) atoms. Both Rb(2)-O(1) bond lengths are 2.72 Å. All Rb(2)-Br(1) bond lengths are 3.66 Å. O(1) is bonded to two equivalent Rb(1) and four equivalent Rb(2) atoms to form corner-sharing ORb6 octahedra. The corner-sharing octahedra are not tilted. Br(1) is bonded in a 9-coordinate geometry to four equivalent Rb(2) and five equivalent Rb(1) atoms.