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DOE OSTI · 1676534

Materials Data on Bi(SbTe2)3 by Materials Project

Abstract

Bi(SbTe2)3 is MAX Phase-like structured and crystallizes in the monoclinic Cm space group. The structure is two-dimensional and consists of two Bi(SbTe2)3 sheets oriented in the (1, 0, 0) direction. Bi3+ is bonded to six Te2- atoms to form BiTe6 octahedra that share corners with three equivalent SbTe6 octahedra, edges with two equivalent BiTe6 octahedra, and edges with seven SbTe6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Bi–Te bond distances ranging from 3.11–3.26 Å. There are three inequivalent Sb3+ sites. In the first Sb3+ site, Sb3+ is bonded to six Te2- atoms to form SbTe6 octahedra that share corners with three equivalent SbTe6 octahedra, edges with four equivalent BiTe6 octahedra, and edges with five SbTe6 octahedra. The corner-sharing octahedral tilt angles are 2°. There are a spread of Sb–Te bond distances ranging from 3.01–3.25 Å. In the second Sb3+ site, Sb3+ is bonded to six Te2- atoms to form SbTe6 octahedra that share corners with three equivalent SbTe6 octahedra, edges with two equivalent BiTe6 octahedra, and edges with seven SbTe6 octahedra. The corner-sharing octahedral tilt angles are 2°. There are a spread of Sb–Te bond distances ranging from 3.04–3.22 Å. In the third Sb3+ site, Sb3+ is bonded to six Te2- atoms to form SbTe6 octahedra that share corners with three equivalent BiTe6 octahedra, an edgeedge with one BiTe6 octahedra, and edges with eight SbTe6 octahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Sb–Te bond distances ranging from 3.03–3.21 Å. There are six inequivalent Te2- sites. In the first Te2- site, Te2- is bonded to one Bi3+ and five Sb3+ atoms to form edge-sharing TeBiSb5 octahedra. In the second Te2- site, Te2- is bonded to two equivalent Bi3+ and four Sb3+ atoms to form edge-sharing TeBi2Sb4 octahedra. In the third Te2- site, Te2- is bonded in a 6-coordinate geometry to two equivalent Bi3+ and one Sb3+ atom. In the fourth Te2- site, Te2- is bonded in a 6-coordinate geometry to one Bi3+ and two equivalent Sb3+ atoms. In the fifth Te2- site, Te2- is bonded in a 6-coordinate geometry to three Sb3+ atoms. In the sixth Te2- site, Te2- is bonded in a 6-coordinate geometry to three Sb3+ atoms.

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2020-05-03. Materials Data on Bi(SbTe2)3 by Materials Project. https://doi.org/10.17188/1676534

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