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DOE OSTI · 1751993

Materials Data on NiAg2Sn3S8 by Materials Project

Abstract

NiAg2Sn3S8 is Spinel-derived structured and crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ni2+ is bonded to six S2- atoms to form NiS6 octahedra that share corners with six equivalent AgS4 trigonal pyramids and edges with six SnS6 octahedra. There are four shorter (2.43 Å) and two longer (2.46 Å) Ni–S bond lengths. Ag1+ is bonded to four S2- atoms to form AgS4 trigonal pyramids that share corners with three equivalent NiS6 octahedra and corners with nine SnS6 octahedra. The corner-sharing octahedra tilt angles range from 46–66°. There are three shorter (2.50 Å) and one longer (2.66 Å) Ag–S bond lengths. There are two inequivalent Sn4+ sites. In the first Sn4+ site, Sn4+ is bonded to six S2- atoms to form SnS6 octahedra that share corners with six equivalent AgS4 trigonal pyramids, edges with two equivalent NiS6 octahedra, and edges with four equivalent SnS6 octahedra. There are four shorter (2.61 Å) and two longer (2.65 Å) Sn–S bond lengths. In the second Sn4+ site, Sn4+ is bonded to six S2- atoms to form SnS6 octahedra that share corners with six equivalent AgS4 trigonal pyramids, edges with two equivalent NiS6 octahedra, and edges with four SnS6 octahedra. There are four shorter (2.60 Å) and two longer (2.65 Å) Sn–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded in a rectangular see-saw-like geometry to one Ni2+, one Ag1+, and two equivalent Sn4+ atoms. In the second S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to one Ag1+ and three Sn4+ atoms. In the third S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to one Ni2+, one Ag1+, and two Sn4+ atoms.

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2020-05-01. Materials Data on NiAg2Sn3S8 by Materials Project. https://doi.org/10.17188/1751993

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36 MATERIALS SCIENCE↗