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DOE OSTI · 1743973

Materials Data on Ba3As2S8O7 by Materials Project

Abstract

Ba3As2S8O7 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to three S+0.25- and five O2- atoms. There are a spread of Ba–S bond distances ranging from 3.20–3.67 Å. There are a spread of Ba–O bond distances ranging from 2.62–2.99 Å. In the second Ba2+ site, Ba2+ is bonded in a 4-coordinate geometry to two S+0.25- and four O2- atoms. There are one shorter (3.29 Å) and one longer (3.58 Å) Ba–S bond lengths. There are a spread of Ba–O bond distances ranging from 2.68–2.79 Å. In the third Ba2+ site, Ba2+ is bonded in a 5-coordinate geometry to one S+0.25- and four O2- atoms. The Ba–S bond length is 3.21 Å. There are a spread of Ba–O bond distances ranging from 2.72–2.81 Å. There are two inequivalent As5+ sites. In the first As5+ site, As5+ is bonded in a distorted single-bond geometry to one O2- atom. The As–O bond length is 1.76 Å. In the second As5+ site, As5+ is bonded in a distorted trigonal non-coplanar geometry to three S+0.25- atoms. There are a spread of As–S bond distances ranging from 2.20–2.70 Å. There are eight inequivalent S+0.25- sites. In the first S+0.25- site, S+0.25- is bonded in a distorted single-bond geometry to one Ba2+, one As5+, one S+0.25-, and one O2- atom. The S–S bond length is 2.05 Å. The S–O bond length is 1.56 Å. In the second S+0.25- site, S+0.25- is bonded in a distorted single-bond geometry to one O2- atom. The S–O bond length is 1.56 Å. In the third S+0.25- site, S+0.25- is bonded in a 2-coordinate geometry to two Ba2+ and one S+0.25- atom. In the fourth S+0.25- site, S+0.25- is bonded in a single-bond geometry to one O2- atom. The S–O bond length is 1.58 Å. In the fifth S+0.25- site, S+0.25- is bonded in a distorted single-bond geometry to one O2- atom. The S–O bond length is 1.60 Å. In the sixth S+0.25- site, S+0.25- is bonded in a 1-coordinate geometry to three Ba2+, one As5+, and two O2- atoms. There are one shorter (3.28 Å) and one longer (3.47 Å) S–O bond lengths. In the seventh S+0.25- site, S+0.25- is bonded in a single-bond geometry to one O2- atom. The S–O bond length is 1.52 Å. In the eighth S+0.25- site, S+0.25- is bonded in a 2-coordinate geometry to one As5+ and one O2- atom. The S–O bond length is 1.58 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ba2+ and one S+0.25- atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two Ba2+ and one As5+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+ and two S+0.25- atoms. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two Ba2+ and one S+0.25- atom. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two Ba2+ and two S+0.25- atoms. In the sixth O2- site, O2- is bonded in a 1-coordinate geometry to two Ba2+ and one S+0.25- atom. In the seventh O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Ba2+ and one S+0.25- atom.

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2020-04-30. Materials Data on Ba3As2S8O7 by Materials Project. https://doi.org/10.17188/1743973

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