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Updated: Nov 20, 2025

Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Unexpected Polymorphism in Bromoantimonate(III) Complexes and Its Effect on Optical Properties
Andrey N Usoltsev1, Taisiya S Sukhikh1, Alexander S Novikov2
1Nikolaev Institute of Inorganic Chemistry SB RAS, Lavrentieva St., 630090 Novosibirsk, Russia.
Abstract:
Reactions of [SbBr6]3- containing HBr solutions with bromide salts of 1,1'-(1,2-ethanediyl)bis(pyridine) (PyC22+) or 1,1'-(1,2-ethanediyl)bis(3,5-dimethylpyridine) (3,5-MePyC22+) initially result in the formation of the deep orange complexes Cat[SbBr5] (1 and 2), featuring unusual Sb···Br interactions in the solid state. In the mother liquor, 1 transforms into discrete binuclear (C2Py)2[Sb2Br10], which demonstrates polymorphism (triclinic 3 and monoclinic 4), while 2 transforms into polymeric (3,5-MePy){[SbBr4]} (5). DFT calculations reveal that the system of noncovalent Sb···Br contacts may be responsible for the appearance of the observed optical properties (unusual deep orange coloring).
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