ScTlSe2 is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. Sc(1) is bonded to six equivalent Se(1) atoms to form edge-sharing ScSe6 octahedra. Tl(1) is bonded in a 6-coordinate geometry to six equivalent Se(1) atoms. Se(1) is bonded to three equivalent Sc(1) and three equivalent Tl(1) atoms to form a mixture of distorted corner and edge-sharing SeSc3Tl3 octahedra. The corner-sharing octahedra are not tilted.
ScTlSe2 is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. Sc(1) is bonded to six equivalent Se(1) atoms to form edge-sharing ScSe6 octahedra. All Sc(1)-Se(1) bond lengths are 2.74 Å. Tl(1) is bonded in a 6-coordinate geometry to six equivalent Se(1) atoms. All Tl(1)-Se(1) bond lengths are 3.28 Å. Se(1) is bonded to three equivalent Sc(1) and three equivalent Tl(1) atoms to form a mixture of distorted corner and edge-sharing SeSc3Tl3 octahedra. The corner-sharing octahedra are not tilted.