YBaCu2O5 crystallizes in the tetragonal P4/mmm space group. Ba(1) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, and faces with eight equivalent Cu(1)O5 square pyramids. Y(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. Cu(1) is bonded to one O(2) and four equivalent O(1) atoms to form CuO5 square pyramids that share corners with five equivalent Cu(1)O5 square pyramids and faces with four equivalent Ba(1)O12 cuboctahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Y(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 corner and edge-sharing OBa4Cu2 octahedra. The corner-sharing octahedra are not tilted.
YBaCu2O5 crystallizes in the tetragonal P4/mmm space group. Ba(1) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, and faces with eight equivalent Cu(1)O5 square pyramids. All Ba(1)-O(2) bond lengths are 2.75 Å. All Ba(1)-O(1) bond lengths are 3.08 Å. Y(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. All Y(1)-O(1) bond lengths are 2.40 Å. Cu(1) is bonded to one O(2) and four equivalent O(1) atoms to form CuO5 square pyramids that share corners with five equivalent Cu(1)O5 square pyramids and faces with four equivalent Ba(1)O12 cuboctahedra. The Cu(1)-O(2) bond length is 2.04 Å. All Cu(1)-O(1) bond lengths are 1.97 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Y(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 corner and edge-sharing OBa4Cu2 octahedra. The corner-sharing octahedra are not tilted.