Materials Data on Ba5Si(Br3O2)2 by Materials Project

Abstract

Ba5SiO4Br6 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are three inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 2-coordinate geometry to three O2- and six Br1- atoms. There are a spread of Ba–O bond distances ranging from 2.66–2.96 Å. There are a spread of Ba–Br bond distances ranging from 3.29–3.86 Å. In the second Ba2+ site, Ba2+ is bonded in a 8-coordinate geometry to two equivalent O2- and six Br1- atoms. Both Ba–O bond lengths are 2.69 Å. There are a spread of Ba–Br bond distances ranging from 3.20–3.46 Å. In the third Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to two O2- and seven Br1- atoms. There are one shorter (2.64 Å) and one longer (2.74 Å) Ba–O bond lengths. There are a spread of Ba–Br bond distances ranging from 3.24–3.87 Å. Si4+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.65 Å) and two longer (1.67 Å) Si–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three Ba2+ and one Si4+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three Ba2+ and one Si4+ atom. There are four inequivalent Br1- sites. In the first Br1- site, Br1- is bonded to six Ba2+ atoms to form distorted corner-sharing BrBa6 octahedra. The corner-sharing octahedral tilt angles are 21°. In the second Br1- site, Br1- is bonded in a 4-coordinate geometry to four Ba2+ atoms. In the third Br1- site, Br1- is bonded in a 5-coordinate geometry to five Ba2+ atoms. In the fourth Br1- site, Br1- is bonded in a 3-coordinate geometry to six Ba2+ atoms.