DOI: 10.17188/1662638
title: Materials Data on Sn5Ge2(SbTe5)2 by Materials Project

description: Sn5Ge2(SbTe5)2 is Caswellsilverite-derived structured and crystallizes in the trigonal R3m space group. The structure is two-dimensional and consists of three Sn5Ge2(SbTe5)2 sheets oriented in the (0, 0, 1) direction. there are five inequivalent Sn+3.60+ sites. In the first Sn+3.60+ site, Sn+3.60+ is bonded to six Te2- atoms to form SnTe6 octahedra that share corners with three equivalent SnTe6 octahedra, corners with three equivalent GeTe6 octahedra, edges with three equivalent GeTe6 octahedra, and edges with nine SnTe6 octahedra. The corner-sharing octahedra tilt angles range from 8–13°. There are three shorter (3.03 Å) and three longer (3.43 Å) Sn–Te bond lengths. In the second Sn+3.60+ site, Sn+3.60+ is bonded to six Te2- atoms to form a mixture of corner and edge-sharing SnTe6 octahedra. The corner-sharing octahedral tilt angles are 8°. There are three shorter (3.02 Å) and three longer (3.36 Å) Sn–Te bond lengths. In the third Sn+3.60+ site, Sn+3.60+ is bonded to six Te2- atoms to form a mixture of corner and edge-sharing SnTe6 octahedra. The corner-sharing octahedra tilt angles range from 8–9°. There are three shorter (3.01 Å) and three longer (3.33 Å) Sn–Te bond lengths. In the fourth Sn+3.60+ site, Sn+3.60+ is bonded to six Te2- atoms to form a mixture of corner and edge-sharing SnTe6 octahedra. The corner-sharing octahedra tilt angles range from 9–10°. There are three shorter (3.01 Å) and three longer (3.36 Å) Sn–Te bond lengths. In the fifth Sn+3.60+ site, Sn+3.60+ is bonded to six Te2- atoms to form a mixture of corner and edge-sharing SnTe6 octahedra. The corner-sharing octahedral tilt angles are 10°. There are three shorter (2.99 Å) and three longer (3.42 Å) Sn–Te bond lengths. There are two inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded to six Te2- atoms to form GeTe6 octahedra that share corners with three equivalent GeTe6 octahedra, corners with three equivalent SbTe6 octahedra, edges with three equivalent SbTe6 octahedra, and edges with nine GeTe6 octahedra. The corner-sharing octahedra tilt angles range from 5–11°. There are three shorter (2.92 Å) and three longer (3.31 Å) Ge–Te bond lengths. In the second Ge4+ site, Ge4+ is bonded to six Te2- atoms to form GeTe6 octahedra that share corners with three equivalent SnTe6 octahedra, corners with three equivalent GeTe6 octahedra, edges with three equivalent SnTe6 octahedra, and edges with nine GeTe6 octahedra. The corner-sharing octahedra tilt angles range from 11–13°. There are three shorter (2.91 Å) and three longer (3.32 Å) Ge–Te bond lengths. There are two inequivalent Sb3- sites. In the first Sb3- site, Sb3- is bonded to six Te2- atoms to form a mixture of corner and edge-sharing SbTe6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are three shorter (3.02 Å) and three longer (3.34 Å) Sb–Te bond lengths. In the second Sb3- site, Sb3- is bonded to six Te2- atoms to form SbTe6 octahedra that share corners with three equivalent GeTe6 octahedra, corners with three equivalent SbTe6 octahedra, edges with three equivalent GeTe6 octahedra, and edges with nine SbTe6 octahedra. The corner-sharing octahedra tilt angles range from 3–5°. There are three shorter (3.10 Å) and three longer (3.18 Å) Sb–Te bond lengths. There are ten inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to six Ge4+ atoms to form TeGe6 octahedra that share corners with six TeGe3Sb3 octahedra and edges with twelve TeGe6 octahedra. The corner-sharing octahedra tilt angles range from 10–11°. In the second Te2- site, Te2- is bonded to three equivalent Ge4+ and three equivalent Sb3- atoms to form a mixture of corner and edge-sharing TeGe3Sb3 octahedra. The corner-sharing octahedra tilt angles range from 2–10°. In the third Te2- site, Te2- is bonded to six Sb3- atoms to form TeSb6 octahedra that share corners with three equivalent TeGe3Sb3 octahedra and edges with nine TeSb6 octahedra. The corner-sharing octahedral tilt angles are 2°. In the fourth Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent Sb3- atoms. In the fifth Te2- site, Te2- is bonded in a 3-coordinate geometry to three equivalent Sn+3.60+ atoms. In the sixth Te2- site, Te2- is bonded to six Sn+3.60+ atoms to form a mixture of corner and edge-sharing TeSn6 octahedra. The corner-sharing octahedral tilt angles are 9°. In the seventh Te2- site, Te2- is bonded to six Sn+3.60+ atoms to form a mixture of corner and edge-sharing TeSn6 octahedra. The corner-sharing octahedral tilt angles are 8°. In the eighth Te2- site, Te2- is bonded to six Sn+3.60+ atoms to form a mixture of corner and edge-sharing TeSn6 octahedra. The corner-sharing octahedra tilt angles range from 8–9°. In the ninth Te2- site, Te2- is bonded to three equivalent Sn+3.60+ and three equivalent Ge4+ atoms to form a mixture of corner and edge-sharing TeSn3Ge3 octahedra. The corner-sharing octahedra tilt angles range from 9–11°. In the tenth Te2- site, Te2- is bonded to six Sn+3.60+ atoms to form a mixture of corner and edge-sharing TeSn6 octahedra. The corner-sharing octahedra tilt angles range from 8–9°.