Materials Data on Ba2CuBrO2 by Materials Project
Ba2CuO2Br crystallizes in the trigonal R3m space group. The structure is three-dimensional. Ba2+ is bonded in a distorted trigonal non-coplanar geometry to three equivalent O2- and three equivalent Br1- atoms. All Ba–O bond lengths are 2.60 Å. All Ba–Br bond lengths are 3.49 Å. Cu1+ is bonded in a linear geometry to two O2- atoms. Both Cu–O bond lengths are 1.81 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to three equivalent Ba2+ and one Cu1+ atom to form OBa3Cu tetrahedra that share corners with three equivalent BrBa6 octahedra, corners with seven OBa3Cu tetrahedra, and edges with three equivalent BrBa6 octahedra. The corner-sharing octahedral tilt angles are 28°. In the second O2- site, O2- is bonded to three equivalent Ba2+ and one Cu1+ atom to form OBa3Cu tetrahedra that share corners with three equivalent BrBa6 octahedra, corners with seven OBa3Cu tetrahedra, and edges with three equivalent BrBa6 octahedra. The corner-sharing octahedral tilt angles are 28°. All O–Ba bond lengths are 2.60 Å. Br1- is bonded to six equivalent Ba2+ atoms to form distorted BrBa6 octahedra that share corners with six OBa3Cu tetrahedra, edges with six equivalent BrBa6 octahedra, and edges with six OBa3Cu tetrahedra.