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DOE OSTI · 1283050

Materials Data on Ag9(SI)4 by Materials Project

Abstract

Ag9(SI)4 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are nine inequivalent Ag+1.33+ sites. In the first Ag+1.33+ site, Ag+1.33+ is bonded in a 6-coordinate geometry to three equivalent S2- and three equivalent I1- atoms. All Ag–S bond lengths are 2.64 Å. There are one shorter (3.06 Å) and two longer (3.39 Å) Ag–I bond lengths. In the second Ag+1.33+ site, Ag+1.33+ is bonded to six I1- atoms to form a mixture of corner and edge-sharing AgI6 octahedra. The corner-sharing octahedral tilt angles are 2°. There are a spread of Ag–I bond distances ranging from 2.95–3.15 Å. In the third Ag+1.33+ site, Ag+1.33+ is bonded to six I1- atoms to form a mixture of corner and edge-sharing AgI6 octahedra. The corner-sharing octahedra tilt angles range from 1–2°. There are two shorter (2.97 Å) and four longer (3.06 Å) Ag–I bond lengths. In the fourth Ag+1.33+ site, Ag+1.33+ is bonded to six I1- atoms to form a mixture of corner and edge-sharing AgI6 octahedra. The corner-sharing octahedra tilt angles range from 1–9°. There are a spread of Ag–I bond distances ranging from 2.95–3.13 Å. In the fifth Ag+1.33+ site, Ag+1.33+ is bonded to three equivalent S2- and three equivalent I1- atoms to form a mixture of distorted corner and edge-sharing AgS3I3 octahedra. The corner-sharing octahedra tilt angles range from 6–9°. There are two shorter (2.64 Å) and one longer (2.65 Å) Ag–S bond lengths. There are one shorter (3.06 Å) and two longer (3.34 Å) Ag–I bond lengths. In the sixth Ag+1.33+ site, Ag+1.33+ is bonded in a 6-coordinate geometry to six S2- atoms. There are a spread of Ag–S bond distances ranging from 2.51–3.05 Å. In the seventh Ag+1.33+ site, Ag+1.33+ is bonded in a 3-coordinate geometry to three S2- atoms. There are two shorter (2.48 Å) and one longer (2.75 Å) Ag–S bond lengths. In the eighth Ag+1.33+ site, Ag+1.33+ is bonded in a distorted bent 120 degrees geometry to three equivalent S2- atoms. There are two shorter (2.45 Å) and one longer (3.44 Å) Ag–S bond lengths. In the ninth Ag+1.33+ site, Ag+1.33+ is bonded to six S2- atoms to form distorted edge-sharing AgS6 octahedra. There are a spread of Ag–S bond distances ranging from 2.53–3.03 Å. There are four inequivalent S2- sites. In the first S2- site, S2- is bonded to six Ag+1.33+ atoms to form distorted SAg6 octahedra that share corners with three equivalent IAg6 octahedra, edges with three equivalent IAg6 octahedra, and edges with six equivalent SAg6 octahedra. The corner-sharing octahedra tilt angles range from 17–21°. In the second S2- site, S2- is bonded to six Ag+1.33+ atoms to form distorted SAg6 octahedra that share corners with three equivalent IAg6 octahedra, edges with three equivalent IAg6 octahedra, and edges with six equivalent SAg6 octahedra. The corner-sharing octahedra tilt angles range from 18–22°. In the third S2- site, S2- is bonded in a 3-coordinate geometry to five Ag+1.33+ atoms. In the fourth S2- site, S2- is bonded in a 3-coordinate geometry to seven Ag+1.33+ atoms. There are four inequivalent I1- sites. In the first I1- site, I1- is bonded to six Ag+1.33+ atoms to form IAg6 octahedra that share corners with three equivalent SAg6 octahedra, corners with three equivalent IAg6 octahedra, edges with three equivalent SAg6 octahedra, and edges with nine IAg6 octahedra. The corner-sharing octahedra tilt angles range from 3–22°. In the second I1- site, I1- is bonded to six Ag+1.33+ atoms to form a mixture of corner and edge-sharing IAg6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the third I1- site, I1- is bonded to six Ag+1.33+ atoms to form a mixture of corner and edge-sharing IAg6 octahedra. The corner-sharing octahedra tilt angles range from 0–4°. In the fourth I1- site, I1- is bonded to six Ag+1.33+ atoms to form IAg6 octahedra that share corners with three equivalent SAg6 octahedra, corners with three equivalent IAg6 octahedra, edges with three equivalent SAg6 octahedra, and edges with nine IAg6 octahedra. The corner-sharing octahedra tilt angles range from 3–21°.

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2020-07-15. Materials Data on Ag9(SI)4 by Materials Project. https://doi.org/10.17188/1283050

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