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Updated: Nov 2, 2025
06:44
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
69.3K
Structural effects of halogen bonding in iodochalcones
Victoria Hamilton1, Connah Harris1, Charlie L Hall1
1School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom.
Summary
Halogenated chalcones exhibit unique halogen bonding patterns influenced by electron-withdrawing groups. The nitro group induced a switch in bonding, revealing new motifs for crystal engineering applications.
Area of Science:
- Crystal Engineering
- Supramolecular Chemistry
- Organic Chemistry
Background:
- Halogen bonding is a crucial non-covalent interaction in supramolecular chemistry.
- Chalcones are versatile organic molecules with diverse applications.
- Understanding substituent effects on halogen bonding is key for designing functional materials.
Purpose of the Study:
- Investigate the impact of fluorine and nitro group functionalization on halogen bonding in iodochalcones.
- Explore how molecular electrostatic potential influences halogen bond motifs.
- Identify novel halogen bonding interactions in chalcone crystal structures.
Main Methods:
- Single-crystal X-ray diffraction analysis of three functionalized iodochalcones.
- Computational analysis of molecular electrostatic potential and charge distribution.
- Characterization of halogen bond interactions (I...I and I...O).
Main Results:
- The nitro group induced a switch from lateral to linear halogen bonding motifs.
- A positive charge shift around the sigma-hole influenced the preference for linear bonding.
- Observed amphoteric I...I type II halogen bonds, a novel finding in chalcones.
- Identified extended linear chains of I...O2N donor-acceptor halogen bonds.
Conclusions:
- Halogenated chalcones are promising candidates for crystal engineering via halogen bonding.
- Substituent effects significantly modulate halogen bond geometry and strength.
- Novel halogen bonding motifs expand the toolkit for supramolecular assembly.
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