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Updated: Jul 10, 2026
06:44
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Isostructural materials achieved by using structurally equivalent donors and acceptors in halogen-bonded cocrystals
Dominik Cincić1, Tomislav Friscić, William Jones
1Laboratory of General and Inorganic Chemistry, Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, Zagreb 10000, Croatia.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|October 24, 2007
Summary
This study synthesized seven isostructural halogen-bonded cocrystals, demonstrating how molecular structure and donor/acceptor choices influence crystal properties like melting point. Cocrystallization offers a method to control solid-state arrangements and tune physical characteristics.
Area of Science:
- Supramolecular Chemistry
- Materials Science
- Crystallography
Background:
- Halogen bonding is a crucial non-covalent interaction directing molecular assembly in the solid state.
- Controlling crystal structure and physical properties through molecular design remains a significant challenge.
- Cocrystallization offers a versatile strategy to engineer solid-state architectures.
Purpose of the Study:
- To demonstrate the supramolecular and structural equivalence of various halogen-bond donors and acceptors.
- To investigate the impact of compositional changes on halogen bond strength and cocrystal properties.
- To explore cocrystallization as a method to overcome molecular dissimilarities and tune physical properties.
Main Methods:
- Synthesis of seven isostructural halogen-bonded cocrystals using six distinct molecules.
- Systematic variation of halogen-bond donors (iodine and bromine) and acceptors (oxygen, nitrogen, and sulfur).
- Analysis of cocrystal structures and physical properties, focusing on melting point variations.
Main Results:
- Achieved isostructural cocrystals with diverse molecular components, highlighting structural equivalence.
- Demonstrated that compositional differences tune halogen bond strength and nature.
- Observed significant melting point variations (approx. 70°C) by altering donor/acceptor groups without changing crystal structure.
Conclusions:
- Cocrystallization can effectively overcome molecular shape and functional group differences to achieve desired solid-state arrangements.
- Systematic modification of halogen-bond donors and acceptors allows for predictable tuning of cocrystal physical properties, particularly melting point.
- The study provides a framework for designing functional crystalline materials through controlled halogen bonding.
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