Materials Data on Sn(BiTe2)2 by Materials Project
SnBi2Te4 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are five inequivalent Sn2+ sites. In the first Sn2+ site, Sn2+ is bonded to six Te2- atoms to form SnTe6 octahedra that share a cornercorner with one SnTe6 octahedra, corners with five BiTe6 octahedra, edges with four SnTe6 octahedra, and edges with eight BiTe6 octahedra. The corner-sharing octahedra tilt angles range from 2–6°. There are a spread of Sn–Te bond distances ranging from 3.12–3.25 Å. In the second Sn2+ site, Sn2+ is bonded to six Te2- atoms to form SnTe6 octahedra that share a cornercorner with one SnTe6 octahedra, corners with four BiTe6 octahedra, edges with three BiTe6 octahedra, and edges with six SnTe6 octahedra. The corner-sharing octahedra tilt angles range from 6–55°. There are a spread of Sn–Te bond distances ranging from 3.02–3.47 Å. In the third Sn2+ site, Sn2+ is bonded to six Te2- atoms to form SnTe6 octahedra that share a cornercorner with one SnTe6 octahedra, corners with five BiTe6 octahedra, edges with six SnTe6 octahedra, and edges with six BiTe6 octahedra. The corner-sharing octahedra tilt angles range from 2–8°. There are a spread of Sn–Te bond distances ranging from 3.14–3.24 Å. In the fourth Sn2+ site, Sn2+ is bonded to six Te2- atoms to form SnTe6 octahedra that share a cornercorner with one SnTe6 octahedra, corners with two equivalent BiTe6 octahedra, edges with four SnTe6 octahedra, edges with four BiTe6 octahedra, and a faceface with one BiTe6 octahedra. The corner-sharing octahedra tilt angles range from 8–48°. There are a spread of Sn–Te bond distances ranging from 3.05–3.41 Å. In the fifth Sn2+ site, Sn2+ is bonded to six Te2- atoms to form SnTe6 octahedra that share corners with five BiTe6 octahedra, edges with two equivalent SnTe6 octahedra, edges with five BiTe6 octahedra, and a faceface with one BiTe6 octahedra. The corner-sharing octahedra tilt angles range from 3–48°. There are a spread of Sn–Te bond distances ranging from 3.14–3.27 Å. There are ten inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share corners with five BiTe6 octahedra, edges with two equivalent SnTe6 octahedra, and edges with five BiTe6 octahedra. The corner-sharing octahedra tilt angles range from 2–50°. There are a spread of Bi–Te bond distances ranging from 3.03–3.39 Å. In the second Bi3+ site, Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share a cornercorner with one SnTe6 octahedra, corners with two equivalent BiTe6 octahedra, edges with two equivalent SnTe6 octahedra, and edges with six BiTe6 octahedra. The corner-sharing octahedra tilt angles range from 2–49°. There are a spread of Bi–Te bond distances ranging from 3.17–3.20 Å. In the third Bi3+ site, Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share corners with two equivalent SnTe6 octahedra, an edgeedge with one SnTe6 octahedra, and edges with eight BiTe6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are a spread of Bi–Te bond distances ranging from 3.10–3.28 Å. In the fourth Bi3+ site, Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share a cornercorner with one SnTe6 octahedra, corners with two equivalent BiTe6 octahedra, edges with two equivalent SnTe6 octahedra, and edges with seven BiTe6 octahedra. The corner-sharing octahedra tilt angles range from 5–6°. There are a spread of Bi–Te bond distances ranging from 2.98–3.42 Å. In the fifth Bi3+ site, Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share a cornercorner with one SnTe6 octahedra, corners with five BiTe6 octahedra, edges with two equivalent SnTe6 octahedra, and edges with eight BiTe6 octahedra. The corner-sharing octahedra tilt angles range from 2–7°. There are a spread of Bi–Te bond distances ranging from 3.00–3.29 Å. In the sixth Bi3+ site, Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share a cornercorner with one BiTe6 octahedra, corners with two equivalent SnTe6 octahedra, edges with four BiTe6 octahedra, and edges with five SnTe6 octahedra. The corner-sharing octahedra tilt angles range from 5–6°. There are a spread of Bi–Te bond distances ranging from 3.01–3.40 Å. In the seventh Bi3+ site, Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share a cornercorner with one BiTe6 octahedra, corners with two equivalent SnTe6 octahedra, edges with three SnTe6 octahedra, and edges with six BiTe6 octahedra. The corner-sharing octahedra tilt angles range from 2–4°. There are a spread of Bi–Te bond distances ranging from 3.05–3.36 Å. In the eighth Bi3+ site, Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share corners with two equivalent SnTe6 octahedra, corners with two equivalent BiTe6 octahedra, edges with three SnTe6 octahedra, and edges with six BiTe6 octahedra. The corner-sharing octahedra tilt angles range from 2–47°. There are a spread of Bi–Te bond distances ranging from 3.13–3.22 Å. In the ninth Bi3+ site, Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share corners with six SnTe6 octahedra, corners with six BiTe6 octahedra, edges with two equivalent BiTe6 octahedra, and faces with two SnTe6 octahedra. The corner-sharing octahedra tilt angles range from 47–55°. There are a spread of Bi–Te bond distances ranging from 3.08–3.29 Å. In the tenth Bi3+ site, Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share corners with two BiTe6 octahedra, corners with four SnTe6 octahedra, edges with four BiTe6 octahedra, and edges with six SnTe6 octahedra. The corner-sharing octahedra tilt angles range from 2–13°. There are a spread of Bi–Te bond distances ranging from 3.10–3.32 Å. There are twenty inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a distorted rectangular see-saw-like geometry to one Sn2+ and three Bi3+ atoms. In the second Te2- site, Te2- is bonded in a rectangular see-saw-like geometry to one Sn2+ and three Bi3+ atoms. In the third Te2- site, Te2- is bonded in a 3-coordinate geometry to three Bi3+ atoms. In the fourth Te2- site, Te2- is bonded to one Sn2+ and five Bi3+ atoms to form TeSnBi5 octahedra that share a cornercorner with one TeSn4Bi2 octahedra, corners with two equivalent TeBi5 square pyramids, edges with six TeSnBi5 octahedra, and an edgeedge with one TeBi5 square pyramid. The corner-sharing octahedral tilt angles are 1°. In the fifth Te2- site, Te2- is bonded to five Bi3+ atoms to form TeBi5 square pyramids that share corners with two equivalent TeSnBi5 octahedra, edges with three TeSnBi5 octahedra, and edges with two equivalent TeBi5 square pyramids. The corner-sharing octahedral tilt angles are 4°. In the sixth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Bi3+ atoms. In the seventh Te2- site, Te2- is bonded in a 3-coordinate geometry to three Bi3+ atoms. In the eighth Te2- site, Te2- is bonded to three Sn2+ and three Bi3+ atoms to form TeSn3Bi3 octahedra that share corners with three TeSn4Bi2 octahedra and edges with nine TeSnBi5 octahedra. The corner-sharing octahedra tilt angles range from 2–3°. In the ninth Te2- site, Te2- is bonded to two equivalent Sn2+ and four Bi3+ atoms to form TeSn2Bi4 octahedra that share corners with two equivalent TeSn3Bi3 octahedra, edges with seven TeSnBi5 octahedra, and edges with two equivalent TeBi5 square pyramids. The corner-sharing octahedral tilt angles are 3°. In the tenth Te2- site, Te2- is bonded in a 3-coordinate geometry to two equivalent Sn2+ and one Bi3+ atom. In the eleventh Te2- site, Te2- is bonded in a 3-coordinate geometry to three Bi3+ atoms. In the twelfth Te2- site, Te2- is bonded to two equivalent Sn2+ and four Bi3+ atoms to form TeSn2Bi4 octahedra that share corners with two equivalent TeSn4Bi2 octahedra, edges with seven TeSn3Bi3 octahedra, and edges with two equivalent TeSn2Bi3 square pyramids. The corner-sharing octahedral tilt angles are 2°. In the thirteenth Te2- site, Te2- is bonded to four Sn2+ and two equivalent Bi3+ atoms to form TeSn4Bi2 octahedra that share corners with three TeSnBi5 octahedra and edges with nine TeSn3Bi3 octahedra. The corner-sharing octahedra tilt angles range from 1–2°. In the fourteenth Te2- site, Te2- is bonded in a 5-coordinate geometry to three Sn2+ and two equivalent Bi3+ atoms. In the fifteenth Te2- site, Te2- is bonded in a 3-coordinate geometry to three Bi3+ atoms. In the sixteenth Te2- site, Te2- is bonded to two equivalent Sn2+ and three Bi3+ atoms to form TeSn2Bi3 square pyramids that share corners with two equivalent TeSn4Bi2 octahedra, edges with three TeSn2Bi4 octahedra, and edges with two equivalent TeSn2Bi3 square pyramids. The corner-sharing octahedral tilt angles are 5°. In the seventeenth Te2- site, Te2- is bonded to four Sn2+ and two equivalent Bi3+ atoms to form TeSn4Bi2 octahedra that share a cornercorner with one TeSn3Bi3 octahedra, corners with two equivalent TeSn2Bi3 square pyramids, edges with six TeSn2Bi4 octahedra, and an edgeedge with one TeSn2Bi3 square pyramid. The corner-sharing octahedral tilt angles are 2°. In the eighteenth Te2- site, Te2- is bonded in a rectangular see-saw-like geometry to one Sn2+ and three Bi3+ atoms. In the nineteenth Te2- site, Te2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Sn2+ and two Bi3+ atoms. In the twentieth Te2- site, Te2- is bonded in a 5-coordinate geometry to two equivalent Sn2+ and three Bi3+ atoms.