Dy2O2Se crystallizes in the trigonal P-3m1 space group. Dy(1) is bonded in a 7-coordinate geometry to three equivalent Se(1) and four equivalent O(1) atoms. Se(1) is bonded to six equivalent Dy(1) atoms to form SeDy6 octahedra that share corners with twelve equivalent O(1)Dy4 tetrahedra, edges with six equivalent Se(1)Dy6 octahedra, and edges with six equivalent O(1)Dy4 tetrahedra. O(1) is bonded to four equivalent Dy(1) atoms to form ODy4 tetrahedra that share corners with six equivalent Se(1)Dy6 octahedra, corners with six equivalent O(1)Dy4 tetrahedra, edges with three equivalent Se(1)Dy6 octahedra, and edges with three equivalent O(1)Dy4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-48°.
Dy2O2Se crystallizes in the trigonal P-3m1 space group. Dy(1) is bonded in a 7-coordinate geometry to three equivalent Se(1) and four equivalent O(1) atoms. All Dy(1)-Se(1) bond lengths are 2.96 Å. There is one shorter (2.27 Å) and three longer (2.28 Å) Dy(1)-O(1) bond lengths. Se(1) is bonded to six equivalent Dy(1) atoms to form SeDy6 octahedra that share corners with twelve equivalent O(1)Dy4 tetrahedra, edges with six equivalent Se(1)Dy6 octahedra, and edges with six equivalent O(1)Dy4 tetrahedra. O(1) is bonded to four equivalent Dy(1) atoms to form ODy4 tetrahedra that share corners with six equivalent Se(1)Dy6 octahedra, corners with six equivalent O(1)Dy4 tetrahedra, edges with three equivalent Se(1)Dy6 octahedra, and edges with three equivalent O(1)Dy4 tetrahedra. The corner-sharing octahedral tilt angles range from 27-48°.