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DOE OSTI · 1738968

Materials Data on Sr2B5BrO9 by Materials Project

Abstract

Sr2B5O9Br crystallizes in the orthorhombic Pnn2 space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to six O2- and two Br1- atoms. There are a spread of Sr–O bond distances ranging from 2.52–2.80 Å. There are one shorter (3.01 Å) and one longer (3.12 Å) Sr–Br bond lengths. In the second Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to seven O2- and two Br1- atoms. There are a spread of Sr–O bond distances ranging from 2.59–3.23 Å. There are one shorter (3.06 Å) and one longer (3.08 Å) Sr–Br bond lengths. There are five inequivalent B3+ sites. In the first B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There is one shorter (1.48 Å) and three longer (1.49 Å) B–O bond length. In the second B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of B–O bond distances ranging from 1.37–1.39 Å. In the third B3+ site, B3+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.37 Å) and two longer (1.38 Å) B–O bond length. In the fourth B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.46–1.50 Å. In the fifth B3+ site, B3+ is bonded to four O2- atoms to form corner-sharing BO4 tetrahedra. There are a spread of B–O bond distances ranging from 1.46–1.52 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sr2+ and two B3+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two Sr2+ and two B3+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Sr2+ and two B3+ atoms. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sr2+ and two B3+ atoms. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Sr2+ and two B3+ atoms. In the sixth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sr2+ and two B3+ atoms. In the seventh O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Sr2+ and two B3+ atoms. In the eighth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Sr2+ and two B3+ atoms. In the ninth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two Sr2+ and two B3+ atoms. There are two inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 4-coordinate geometry to four Sr2+ atoms. In the second Br1- site, Br1- is bonded in a distorted rectangular see-saw-like geometry to four Sr2+ atoms.

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2020-05-02. Materials Data on Sr2B5BrO9 by Materials Project. https://doi.org/10.17188/1738968

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