Materials Data on SmTlSe2 by Materials Project
TlSmSe2 is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Sm3+ is bonded to six equivalent Se2- atoms to form SmSe6 octahedra that share corners with six equivalent TlSe6 octahedra, edges with six equivalent SmSe6 octahedra, and edges with six equivalent TlSe6 octahedra. The corner-sharing octahedral tilt angles are 9°. All Sm–Se bond lengths are 2.96 Å. Tl1+ is bonded to six equivalent Se2- atoms to form TlSe6 octahedra that share corners with six equivalent SmSe6 octahedra, edges with six equivalent SmSe6 octahedra, and edges with six equivalent TlSe6 octahedra. The corner-sharing octahedral tilt angles are 9°. All Tl–Se bond lengths are 3.35 Å. Se2- is bonded to three equivalent Sm3+ and three equivalent Tl1+ atoms to form a mixture of edge and corner-sharing SeSm3Tl3 octahedra. The corner-sharing octahedral tilt angles are 0°.