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DOE OSTI · 1684369

Materials Data on Ti5S8 by Materials Project

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Abstract

Ti5S8 crystallizes in the trigonal R3m space group. The structure is two-dimensional and consists of three Ti3S4 sheets oriented in the (0, 0, 1) direction and six TiS2 sheets oriented in the (0, 0, 1) direction. In each Ti3S4 sheet, there are three inequivalent Ti+3.20+ sites. In the first Ti+3.20+ site, Ti+3.20+ is bonded to six S2- atoms to form a mixture of edge, face, and corner-sharing TiS6 octahedra. The corner-sharing octahedral tilt angles are 45°. There are three shorter (2.41 Å) and three longer (2.54 Å) Ti–S bond lengths. In the second Ti+3.20+ site, Ti+3.20+ is bonded to six S2- atoms to form a mixture of edge and corner-sharing TiS6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are three shorter (2.42 Å) and three longer (2.47 Å) Ti–S bond lengths. In the third Ti+3.20+ site, Ti+3.20+ is bonded to six S2- atoms to form a mixture of edge, face, and corner-sharing TiS6 octahedra. The corner-sharing octahedra tilt angles range from 3–45°. There are three shorter (2.38 Å) and three longer (2.58 Å) Ti–S bond lengths. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to six Ti+3.20+ atoms to form a mixture of distorted edge and corner-sharing STi6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 6°. In the second S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Ti+3.20+ atoms. In the third S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Ti+3.20+ atoms. In the fourth S2- site, S2- is bonded to six Ti+3.20+ atoms to form a mixture of edge and corner-sharing STi6 octahedra. In each TiS2 sheet, Ti+3.20+ is bonded to six S2- atoms to form edge-sharing TiS6 octahedra. All Ti–S bond lengths are 2.43 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Ti+3.20+ atoms. In the second S2- site, S2- is bonded in a distorted T-shaped geometry to three equivalent Ti+3.20+ atoms.

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36 MATERIALS SCIENCEcrystal structureS-TiTi5S8

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2020-05-03. Materials Data on Ti5S8 by Materials Project. https://doi.org/10.17188/1684369

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