Materials Data on Sn4GeTe4Se by Materials Project
Sn4GeTe4Se is Caswellsilverite-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are four inequivalent Sn2+ sites. In the first Sn2+ site, Sn2+ is bonded to three equivalent Te2- and three equivalent Se2- atoms to form distorted SnTe3Se3 octahedra that share corners with three equivalent SnTe6 octahedra, corners with three equivalent GeTe3Se3 octahedra, edges with three equivalent GeTe3Se3 octahedra, and edges with nine SnTe3Se3 octahedra. The corner-sharing octahedra tilt angles range from 5–6°. All Sn–Te bond lengths are 3.34 Å. All Sn–Se bond lengths are 2.93 Å. In the second Sn2+ site, Sn2+ is bonded to six Te2- atoms to form a mixture of edge and corner-sharing SnTe6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are three shorter (3.07 Å) and three longer (3.32 Å) Sn–Te bond lengths. In the third Sn2+ site, Sn2+ is bonded to six Te2- atoms to form a mixture of edge and corner-sharing SnTe6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are three shorter (3.07 Å) and three longer (3.31 Å) Sn–Te bond lengths. In the fourth Sn2+ site, Sn2+ is bonded to six Te2- atoms to form SnTe6 octahedra that share corners with three equivalent SnTe6 octahedra, corners with three equivalent GeTe3Se3 octahedra, edges with three equivalent GeTe3Se3 octahedra, and edges with nine SnTe6 octahedra. The corner-sharing octahedra tilt angles range from 6–10°. There are three shorter (3.08 Å) and three longer (3.33 Å) Sn–Te bond lengths. Ge2+ is bonded to three equivalent Te2- and three equivalent Se2- atoms to form GeTe3Se3 octahedra that share corners with six SnTe3Se3 octahedra, edges with six SnTe3Se3 octahedra, and edges with six equivalent GeTe3Se3 octahedra. The corner-sharing octahedra tilt angles range from 5–10°. All Ge–Te bond lengths are 2.95 Å. All Ge–Se bond lengths are 3.09 Å. There are four inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to six Sn2+ atoms to form TeSn6 octahedra that share corners with three equivalent TeSn6 octahedra, corners with three equivalent SeSn3Ge3 octahedra, edges with three equivalent SeSn3Ge3 octahedra, and edges with nine TeSn6 octahedra. The corner-sharing octahedra tilt angles range from 6–10°. In the second Te2- site, Te2- is bonded to six Sn2+ atoms to form a mixture of edge and corner-sharing TeSn6 octahedra. The corner-sharing octahedral tilt angles are 6°. In the third Te2- site, Te2- is bonded to six Sn2+ atoms to form a mixture of edge and corner-sharing TeSn6 octahedra. The corner-sharing octahedral tilt angles are 6°. In the fourth Te2- site, Te2- is bonded to three equivalent Sn2+ and three equivalent Ge2+ atoms to form TeSn3Ge3 octahedra that share corners with three equivalent TeSn6 octahedra, corners with three equivalent SeSn3Ge3 octahedra, edges with three equivalent SeSn3Ge3 octahedra, and edges with nine TeSn6 octahedra. The corner-sharing octahedra tilt angles range from 4–6°. Se2- is bonded to three equivalent Sn2+ and three equivalent Ge2+ atoms to form SeSn3Ge3 octahedra that share corners with six TeSn3Ge3 octahedra, edges with six TeSn3Ge3 octahedra, and edges with six equivalent SeSn3Ge3 octahedra. The corner-sharing octahedra tilt angles range from 4–10°.