Ho2BaCuO5 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 11-coordinate geometry to three equivalent O(1), four equivalent O(2), and four equivalent O(3) atoms. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to one O(1), two equivalent O(2), and four equivalent O(3) atoms to form distorted HoO7 pentagonal bipyramids that share corners with five equivalent Cu(1)O5 square pyramids, edges with two equivalent Ho(1)O7 pentagonal bipyramids, and  an edgeedge with one Cu(1)O5 square pyramid. In the second Ho site, Ho(2) is bonded in a 7-coordinate geometry to one O(1), two equivalent O(3), and four equivalent O(2) atoms. Cu(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted CuO5 square pyramids that share corners with five equivalent Ho(1)O7 pentagonal bipyramids and  an edgeedge with one Ho(1)O7 pentagonal bipyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Ba(1), one Ho(1), one Ho(2), and one Cu(1) atom to form a mixture of corner and edge-sharing OBa3Ho2Cu octahedra. The corner-sharing octahedral tilt angles are 5°. In the second O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Ba(1), one Ho(1), two equivalent Ho(2), and one Cu(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Ho(2), two equivalent Ho(1), and one Cu(1) atom.
Ho2BaCuO5 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 11-coordinate geometry to three equivalent O(1), four equivalent O(2), and four equivalent O(3) atoms. There is one shorter (2.64 Å) and two longer (2.85 Å) Ba(1)-O(1) bond lengths. There are two shorter (2.98 Å) and two longer (3.01 Å) Ba(1)-O(2) bond lengths. There are two shorter (3.12 Å) and two longer (3.30 Å) Ba(1)-O(3) bond lengths. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded to one O(1), two equivalent O(2), and four equivalent O(3) atoms to form distorted HoO7 pentagonal bipyramids that share corners with five equivalent Cu(1)O5 square pyramids, edges with two equivalent Ho(1)O7 pentagonal bipyramids, and  an edgeedge with one Cu(1)O5 square pyramid. The Ho(1)-O(1) bond length is 2.27 Å. Both Ho(1)-O(2) bond lengths are 2.39 Å. There are two shorter (2.30 Å) and two longer (2.36 Å) Ho(1)-O(3) bond lengths. In the second Ho site, Ho(2) is bonded in a 7-coordinate geometry to one O(1), two equivalent O(3), and four equivalent O(2) atoms. The Ho(2)-O(1) bond length is 2.29 Å. Both Ho(2)-O(3) bond lengths are 2.31 Å. There are two shorter (2.33 Å) and two longer (2.38 Å) Ho(2)-O(2) bond lengths. Cu(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted CuO5 square pyramids that share corners with five equivalent Ho(1)O7 pentagonal bipyramids and  an edgeedge with one Ho(1)O7 pentagonal bipyramid. The Cu(1)-O(1) bond length is 2.31 Å. Both Cu(1)-O(2) bond lengths are 2.03 Å. Both Cu(1)-O(3) bond lengths are 2.00 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Ba(1), one Ho(1), one Ho(2), and one Cu(1) atom to form a mixture of corner and edge-sharing OBa3Ho2Cu octahedra. The corner-sharing octahedral tilt angles are 5°. In the second O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Ba(1), one Ho(1), two equivalent Ho(2), and one Cu(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Ho(2), two equivalent Ho(1), and one Cu(1) atom.