RbSmSe2 is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. Rb(1) is bonded to six equivalent Se(1) atoms to form distorted RbSe6 octahedra that share corners with six equivalent Sm(1)Se6 octahedra, edges with six equivalent Rb(1)Se6 octahedra, and edges with six equivalent Sm(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 11°. Sm(1) is bonded to six equivalent Se(1) atoms to form SmSe6 octahedra that share corners with six equivalent Rb(1)Se6 octahedra, edges with six equivalent Rb(1)Se6 octahedra, and edges with six equivalent Sm(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 11°. Se(1) is bonded to three equivalent Rb(1) and three equivalent Sm(1) atoms to form a mixture of corner and edge-sharing SeRb3Sm3 octahedra. The corner-sharing octahedra are not tilted.
RbSmSe2 is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. Rb(1) is bonded to six equivalent Se(1) atoms to form distorted RbSe6 octahedra that share corners with six equivalent Sm(1)Se6 octahedra, edges with six equivalent Rb(1)Se6 octahedra, and edges with six equivalent Sm(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 11°. All Rb(1)-Se(1) bond lengths are 3.45 Å. Sm(1) is bonded to six equivalent Se(1) atoms to form SmSe6 octahedra that share corners with six equivalent Rb(1)Se6 octahedra, edges with six equivalent Rb(1)Se6 octahedra, and edges with six equivalent Sm(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 11°. All Sm(1)-Se(1) bond lengths are 2.95 Å. Se(1) is bonded to three equivalent Rb(1) and three equivalent Sm(1) atoms to form a mixture of corner and edge-sharing SeRb3Sm3 octahedra. The corner-sharing octahedra are not tilted.