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DOE OSTI · 1662239

Materials Data on Ga2Fe2S5 by Materials Project

Abstract

Fe2Ga2S5 is beta indium sulfide-derived structured and crystallizes in the trigonal P-3m1 space group. The structure is two-dimensional and consists of one Fe2Ga2S5 sheet oriented in the (0, 0, 1) direction. Fe2+ is bonded to six S2- atoms to form FeS6 octahedra that share corners with three equivalent FeS6 octahedra, corners with three equivalent GaS4 tetrahedra, and edges with nine equivalent FeS6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are three shorter (2.47 Å) and three longer (2.50 Å) Fe–S bond lengths. Ga3+ is bonded to four S2- atoms to form GaS4 tetrahedra that share corners with three equivalent FeS6 octahedra and corners with six equivalent GaS4 tetrahedra. The corner-sharing octahedral tilt angles are 58°. There are one shorter (2.23 Å) and three longer (2.35 Å) Ga–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded to six equivalent Fe2+ atoms to form SFe6 octahedra that share corners with six equivalent SGaFe3 trigonal pyramids, edges with six equivalent SFe6 octahedra, and edges with six equivalent SGaFe3 trigonal pyramids. In the second S2- site, S2- is bonded to three equivalent Fe2+ and one Ga3+ atom to form distorted SGaFe3 trigonal pyramids that share corners with three equivalent SFe6 octahedra, corners with six equivalent SGaFe3 trigonal pyramids, and edges with three equivalent SFe6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the third S2- site, S2- is bonded in a distorted trigonal non-coplanar geometry to three equivalent Ga3+ atoms.

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2020-07-16. Materials Data on Ga2Fe2S5 by Materials Project. https://doi.org/10.17188/1662239

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36 MATERIALS SCIENCE↗