(H3O)3Sb2Br9: the first member of the M3E2X9 structure family with oxonium cations

Jen Hui Chang; Thomas Doert; Michael Ruck

doi:10.1107/S2053229616017198

(H₃O)₃Sb₂Br₉: the first member of the M₃E₂X₉ structure family with oxonium cations

Acta Crystallogr C Struct Chem. 2016 Dec 1;72(Pt 12):966-970. doi: 10.1107/S2053229616017198. Epub 2016 Nov 7.

Authors

Jen Hui Chang¹, Thomas Doert¹, Michael Ruck¹

Affiliation

¹ Department of Chemistry and Food Chemistry, Technische Universitt Dresden, Helmholtzstrasse 10, Dresden, Sachsen 01069, Germany.

PMID: 27918298
DOI: 10.1107/S2053229616017198

Abstract

(H₃O)₃Sb₂Br₉ [trihydroxonium enneabromidodiantimonate(III)] is the first representative of the M₃E₂X₉ family (M = cation, E = Sb and Bi, and X = Br and I) with oxonium cations. The metastable compound was obtained in trace amounts from a solution of CsBr and SbBr₃ in concentrated aqueous HBr. Single crystals were isolated from the mother liquor and investigated by single-crystal X-ray diffraction at 100 K. (H₃O)₃Sb₂Br₉ crystallizes with the Tl₃Bi₂I₉ structure type, which is a distorted defect variant of cubic perovskite. The crystal structure comprises characteristic ²_∞[SbBr₃Br_3/2] double layers of corner-sharing SbBr₆ octahedra with a [001] stacking direction. Due to the small size of the H₃O⁺ cation and O-H...Br hydrogen bonding, the octahedra are tilted.

Keywords: Tl3Bi2I9 structure type; crystal structure; defect perovskite structure; hydrogen bonding; oxonium cations; sphere close AX3 packing.