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DOE OSTI · 1269926

Materials Data on Bi14Te13S8 by Materials Project

Abstract

Bi14Te13S8 is Calaverite-derived structured and crystallizes in the trigonal R-3 space group. The structure is two-dimensional and consists of three Bi14Te13S8 sheets oriented in the (0, 0, 1) direction. there are three inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded to three equivalent Te2- and three equivalent S2- atoms to form a mixture of corner and edge-sharing BiTe3S3 octahedra. The corner-sharing octahedral tilt angles are 2°. All Bi–Te bond lengths are 3.06 Å. All Bi–S bond lengths are 3.07 Å. In the second Bi3+ site, Bi3+ is bonded to four Te2- and two equivalent S2- atoms to form a mixture of corner and edge-sharing BiTe4S2 octahedra. The corner-sharing octahedra tilt angles range from 0–5°. There are a spread of Bi–Te bond distances ranging from 3.05–3.18 Å. There are one shorter (3.06 Å) and one longer (3.09 Å) Bi–S bond lengths. In the third Bi3+ site, Bi3+ is bonded to two Te2- and four S2- atoms to form BiTe2S4 octahedra that share corners with three BiTe4S2 octahedra and edges with nine BiTe3S3 octahedra. The corner-sharing octahedra tilt angles range from 1–5°. Both Bi–Te bond lengths are 3.08 Å. There are a spread of Bi–S bond distances ranging from 2.76–3.03 Å. There are three inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a 3-coordinate geometry to three Bi3+ atoms. In the second Te2- site, Te2- is bonded in a 3-coordinate geometry to three Bi3+ atoms. In the third Te2- site, Te2- is bonded to six equivalent Bi3+ atoms to form TeBi6 octahedra that share edges with six equivalent SBi6 octahedra. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded to six Bi3+ atoms to form SBi6 octahedra that share an edgeedge with one TeBi6 octahedra and edges with five equivalent SBi6 octahedra. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three equivalent Bi3+ atoms.

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2020-04-30. Materials Data on Bi14Te13S8 by Materials Project. https://doi.org/10.17188/1269926

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36 MATERIALS SCIENCE↗