Dy2Y2O5 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Dy sites. In the first Dy site, Dy(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. In the second Dy site, Dy(2) is bonded in a square co-planar geometry to four equivalent O(2) atoms. Y(1) is bonded in a 5-coordinate geometry to one O(2) and four equivalent O(1) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Dy(1) and two equivalent Y(1) atoms to form ODy2Y2 tetrahedra that share corners with two equivalent O(2)Dy4Y2 octahedra, corners with ten equivalent O(1)Dy2Y2 tetrahedra, and edges with five equivalent O(1)Dy2Y2 tetrahedra. The corner-sharing octahedral tilt angles are 64°. In the second O site, O(2) is bonded to four equivalent Dy(2) and two equivalent Y(1) atoms to form ODy4Y2 octahedra that share corners with four equivalent O(2)Dy4Y2 octahedra, corners with eight equivalent O(1)Dy2Y2 tetrahedra, and edges with four equivalent O(2)Dy4Y2 octahedra. The corner-sharing octahedra are not tilted.
Dy2Y2O5 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Dy sites. In the first Dy site, Dy(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. All Dy(1)-O(1) bond lengths are 2.39 Å. In the second Dy site, Dy(2) is bonded in a square co-planar geometry to four equivalent O(2) atoms. All Dy(2)-O(2) bond lengths are 2.76 Å. Y(1) is bonded in a 5-coordinate geometry to one O(2) and four equivalent O(1) atoms. The Y(1)-O(2) bond length is 2.60 Å. All Y(1)-O(1) bond lengths are 2.17 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Dy(1) and two equivalent Y(1) atoms to form ODy2Y2 tetrahedra that share corners with two equivalent O(2)Dy4Y2 octahedra, corners with ten equivalent O(1)Dy2Y2 tetrahedra, and edges with five equivalent O(1)Dy2Y2 tetrahedra. The corner-sharing octahedral tilt angles are 64°. In the second O site, O(2) is bonded to four equivalent Dy(2) and two equivalent Y(1) atoms to form ODy4Y2 octahedra that share corners with four equivalent O(2)Dy4Y2 octahedra, corners with eight equivalent O(1)Dy2Y2 tetrahedra, and edges with four equivalent O(2)Dy4Y2 octahedra. The corner-sharing octahedra are not tilted.