BaCuO2 crystallizes in the orthorhombic Pbcm space group. Ba(1) is bonded in a 7-coordinate geometry to three equivalent O(1) and four equivalent O(2) atoms. Cu(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form corner-sharing CuO4 trigonal pyramids. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to three equivalent Ba(1) and two equivalent Cu(1) atoms. In the second O site, O(2) is bonded to four equivalent Ba(1) and two equivalent Cu(1) atoms to form a mixture of edge, face, and corner-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles are 58°.
BaCuO2 crystallizes in the orthorhombic Pbcm space group. Ba(1) is bonded in a 7-coordinate geometry to three equivalent O(1) and four equivalent O(2) atoms. There is one shorter (2.70 Å) and two longer (3.04 Å) Ba(1)-O(1) bond lengths. All Ba(1)-O(2) bond lengths are 2.73 Å. Cu(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form corner-sharing CuO4 trigonal pyramids. Both Cu(1)-O(1) bond lengths are 1.93 Å. Both Cu(1)-O(2) bond lengths are 2.04 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to three equivalent Ba(1) and two equivalent Cu(1) atoms. In the second O site, O(2) is bonded to four equivalent Ba(1) and two equivalent Cu(1) atoms to form a mixture of edge, face, and corner-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles are 58°.