Eu2BaCuO5 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 11-coordinate geometry to three equivalent O(2), four equivalent O(1), and four equivalent O(3) atoms. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded to one O(2), two equivalent O(1), and four equivalent O(3) atoms to form distorted EuO7 pentagonal bipyramids that share corners with five equivalent Cu(1)O5 square pyramids, edges with two equivalent Eu(1)O7 pentagonal bipyramids, and  an edgeedge with one Cu(1)O5 square pyramid. In the second Eu site, Eu(2) is bonded in a 7-coordinate geometry to one O(2), two equivalent O(3), and four equivalent O(1) atoms. Cu(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form distorted CuO5 square pyramids that share corners with five equivalent Eu(1)O7 pentagonal bipyramids and  an edgeedge with one Eu(1)O7 pentagonal bipyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Ba(1), one Eu(1), two equivalent Eu(2), and one Cu(1) atom. In the second O site, O(2) is bonded to three equivalent Ba(1), one Eu(1), one Eu(2), and one Cu(1) atom to form a mixture of corner and edge-sharing OBa3Eu2Cu octahedra. The corner-sharing octahedral tilt angles are 3°. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Eu(2), two equivalent Eu(1), and one Cu(1) atom.
Eu2BaCuO5 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 11-coordinate geometry to three equivalent O(2), four equivalent O(1), and four equivalent O(3) atoms. There is one shorter (2.64 Å) and two longer (2.90 Å) Ba(1)-O(2) bond lengths. There are two shorter (3.05 Å) and two longer (3.10 Å) Ba(1)-O(1) bond lengths. There are two shorter (3.11 Å) and two longer (3.36 Å) Ba(1)-O(3) bond lengths. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded to one O(2), two equivalent O(1), and four equivalent O(3) atoms to form distorted EuO7 pentagonal bipyramids that share corners with five equivalent Cu(1)O5 square pyramids, edges with two equivalent Eu(1)O7 pentagonal bipyramids, and  an edgeedge with one Cu(1)O5 square pyramid. The Eu(1)-O(2) bond length is 2.36 Å. Both Eu(1)-O(1) bond lengths are 2.53 Å. There are two shorter (2.40 Å) and two longer (2.51 Å) Eu(1)-O(3) bond lengths. In the second Eu site, Eu(2) is bonded in a 7-coordinate geometry to one O(2), two equivalent O(3), and four equivalent O(1) atoms. The Eu(2)-O(2) bond length is 2.37 Å. Both Eu(2)-O(3) bond lengths are 2.43 Å. There are two shorter (2.41 Å) and two longer (2.43 Å) Eu(2)-O(1) bond lengths. Cu(1) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form distorted CuO5 square pyramids that share corners with five equivalent Eu(1)O7 pentagonal bipyramids and  an edgeedge with one Eu(1)O7 pentagonal bipyramid. The Cu(1)-O(2) bond length is 2.36 Å. Both Cu(1)-O(1) bond lengths are 1.98 Å. Both Cu(1)-O(3) bond lengths are 1.94 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to two equivalent Ba(1), one Eu(1), two equivalent Eu(2), and one Cu(1) atom. In the second O site, O(2) is bonded to three equivalent Ba(1), one Eu(1), one Eu(2), and one Cu(1) atom to form a mixture of corner and edge-sharing OBa3Eu2Cu octahedra. The corner-sharing octahedral tilt angles are 3°. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Eu(2), two equivalent Eu(1), and one Cu(1) atom.