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Updated: Mar 13, 2026
06:44
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
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[NMe4 ][I4 Br5 ]: A new Iodobromide from an Ionic Liquid with Halogen-Halogen Interactions
Lisa Mann1, Patrick Voßnacker1, Carsten Müller2
1Fachbereich Biologie, Chemie, Pharmazie, Institut für Chemie und Biochemie-Anorganische Chemie, Fabeckstraße 34/36, 14195, Berlin, Germany.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|October 27, 2016
Summary
Tetramethylammonium tetraiodopentabromide, a novel iodobromide, was synthesized in ionic liquid and dichloromethane. Its unique structure, featuring halogen-halogen interactions, was confirmed using spectroscopy and X-ray analysis.
Area of Science:
- Inorganic Chemistry
- Materials Science
- Crystallography
Background:
- Iodobromides are a class of polyhalogen anions.
- Synthesis and structural characterization of novel polyhalogen compounds are of interest in inorganic chemistry.
Purpose of the Study:
- To synthesize and characterize a new iodobromide, tetramethylammonium tetraiodopentabromide ([NMe4][I4Br5]).
- To investigate its structural motifs and bonding characteristics.
Main Methods:
- Synthesis in ionic liquid and dichloromethane.
- Single crystal X-ray diffraction for structure determination.
- Raman spectroscopy for characterization.
- Conductivity measurements and thermogravimetric analysis.
- Quantum-chemical calculations for structural discussion.
Main Results:
- The first synthesis and crystallization of tetramethylammonium tetraiodopentabromide ([NMe4][I4Br5]) were achieved.
- The compound exhibits unique structural motives, described as [(I2Br3)− ⋅ 2 IBr], with IBr units linked by halogen-halogen interactions.
- Characterization confirmed the V-shaped [I2Br3]− anion and the presence of additional IBr units.
Conclusions:
- Tetramethylammonium tetraiodopentabromide represents a new class of iodobromides with novel structural features.
- Halogen-halogen interactions play a significant role in stabilizing the observed structure.
- The study provides insights into the synthesis and structural diversity of polyhalogen compounds.
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