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DOE OSTI · 1662792

Materials Data on Rb2Ba6Sb5HO by Materials Project

Abstract

Rb2Ba6Sb5HO crystallizes in the tetragonal I4/mcm space group. The structure is three-dimensional. Rb1+ is bonded in a 8-coordinate geometry to six equivalent Sb+2.60- and two equivalent H1+ atoms. There are four shorter (3.91 Å) and two longer (4.00 Å) Rb–Sb bond lengths. Both Rb–H bond lengths are 3.32 Å. There are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a single-bond geometry to five Sb+2.60- and one O2- atom. There are a spread of Ba–Sb bond distances ranging from 3.59–3.86 Å. The Ba–O bond length is 2.56 Å. In the second Ba2+ site, Ba2+ is bonded to four equivalent Sb+2.60- and one H1+ atom to form distorted corner-sharing BaSb4H square pyramids. All Ba–Sb bond lengths are 3.58 Å. The Ba–H bond length is 2.66 Å. There are two inequivalent Sb+2.60- sites. In the first Sb+2.60- site, Sb+2.60- is bonded in a 9-coordinate geometry to three equivalent Rb1+, five Ba2+, and one Sb+2.60- atom. The Sb–Sb bond length is 2.94 Å. In the second Sb+2.60- site, Sb+2.60- is bonded in a 8-coordinate geometry to eight equivalent Ba2+ atoms. H1+ is bonded in a linear geometry to four equivalent Rb1+ and two equivalent Ba2+ atoms. O2- is bonded in a tetrahedral geometry to four equivalent Ba2+ atoms.

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2020-04-30. Materials Data on Rb2Ba6Sb5HO by Materials Project. https://doi.org/10.17188/1662792

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36 MATERIALS SCIENCE↗