Eu2O2S crystallizes in the trigonal P-3m1 space group. Eu(1) is bonded in a 7-coordinate geometry to three equivalent S(1) and four equivalent O(1) atoms. S(1) is bonded to six equivalent Eu(1) atoms to form SEu6 octahedra that share corners with twelve equivalent O(1)Eu4 tetrahedra, edges with six equivalent S(1)Eu6 octahedra, and edges with six equivalent O(1)Eu4 tetrahedra. O(1) is bonded to four equivalent Eu(1) atoms to form OEu4 tetrahedra that share corners with six equivalent S(1)Eu6 octahedra, corners with six equivalent O(1)Eu4 tetrahedra, edges with three equivalent S(1)Eu6 octahedra, and edges with three equivalent O(1)Eu4 tetrahedra. The corner-sharing octahedral tilt angles range from 25-50°.
Eu2O2S crystallizes in the trigonal P-3m1 space group. Eu(1) is bonded in a 7-coordinate geometry to three equivalent S(1) and four equivalent O(1) atoms. All Eu(1)-S(1) bond lengths are 2.95 Å. There are three shorter (2.33 Å) and one longer (2.35 Å) Eu(1)-O(1) bond length. S(1) is bonded to six equivalent Eu(1) atoms to form SEu6 octahedra that share corners with twelve equivalent O(1)Eu4 tetrahedra, edges with six equivalent S(1)Eu6 octahedra, and edges with six equivalent O(1)Eu4 tetrahedra. O(1) is bonded to four equivalent Eu(1) atoms to form OEu4 tetrahedra that share corners with six equivalent S(1)Eu6 octahedra, corners with six equivalent O(1)Eu4 tetrahedra, edges with three equivalent S(1)Eu6 octahedra, and edges with three equivalent O(1)Eu4 tetrahedra. The corner-sharing octahedral tilt angles range from 25-50°.