Gd2HfO5 crystallizes in the orthorhombic Cmcm space group. Gd(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(1), and three equivalent O(2) atoms. Hf(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing HfO6 octahedra. The corner-sharing octahedral tilt angles are 33°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Gd(1) and one Hf(1) atom. In the second O site, O(2) is bonded to three equivalent Gd(1) and one Hf(1) atom to form OGd3Hf tetrahedra that share  a cornercorner with one O(3)Gd2Hf2 tetrahedra, corners with three equivalent O(2)Gd3Hf tetrahedra, edges with two equivalent O(3)Gd2Hf2 tetrahedra, and edges with two equivalent O(2)Gd3Hf tetrahedra. In the third O site, O(3) is bonded to two equivalent Gd(1) and two equivalent Hf(1) atoms to form distorted OGd2Hf2 tetrahedra that share corners with two equivalent O(3)Gd2Hf2 tetrahedra, corners with two equivalent O(2)Gd3Hf tetrahedra, and edges with four equivalent O(2)Gd3Hf tetrahedra.
Gd2HfO5 crystallizes in the orthorhombic Cmcm space group. Gd(1) is bonded in a 6-coordinate geometry to one O(3), two equivalent O(1), and three equivalent O(2) atoms. The Gd(1)-O(3) bond length is 2.50 Å. There is one shorter (2.23 Å) and one longer (2.29 Å) Gd(1)-O(1) bond length. There are two shorter (2.24 Å) and one longer (2.45 Å) Gd(1)-O(2) bond length. Hf(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing HfO6 octahedra. The corner-sharing octahedral tilt angles are 33°. Both Hf(1)-O(1) bond lengths are 2.03 Å. Both Hf(1)-O(2) bond lengths are 2.17 Å. Both Hf(1)-O(3) bond lengths are 2.16 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Gd(1) and one Hf(1) atom. In the second O site, O(2) is bonded to three equivalent Gd(1) and one Hf(1) atom to form OGd3Hf tetrahedra that share  a cornercorner with one O(3)Gd2Hf2 tetrahedra, corners with three equivalent O(2)Gd3Hf tetrahedra, edges with two equivalent O(3)Gd2Hf2 tetrahedra, and edges with two equivalent O(2)Gd3Hf tetrahedra. In the third O site, O(3) is bonded to two equivalent Gd(1) and two equivalent Hf(1) atoms to form distorted OGd2Hf2 tetrahedra that share corners with two equivalent O(3)Gd2Hf2 tetrahedra, corners with two equivalent O(2)Gd3Hf tetrahedra, and edges with four equivalent O(2)Gd3Hf tetrahedra.