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Updated: Jun 23, 2026
06:44
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Ordo ab Chao: Crystallographic Disorder as a Window into Ionic Liquid Structure
Joseph Cooper1, Marija Scheuren1, Lara I Teodoro1
1Department of Chemistry and Physics, Ave Maria University, Ave Maria, Florida 34142, United States.
Crystal Growth & Design
|June 22, 2026
Summary
Ionic liquids (ILs) often form solids despite their design. Crystallographic disorder in ILs reveals structural insights into their phase behavior and metastable liquid states.
Area of Science:
- Materials Science
- Crystallography
- Physical Chemistry
Background:
- Ionic liquids (ILs) are designed to resist crystallization but frequently form solids with low melting points.
- Crystallographic disorder and metastable liquid states are common in ILs, offering insights into their phase behavior.
Purpose of the Study:
- To investigate the crystallographic features of benzylated ionic liquids.
- To understand how molecular structure influences the crystallization and phase behavior of ILs.
Main Methods:
- Single-crystal X-ray diffraction.
- Computational modeling and statistical analyses.
- Study of benzylated ionic liquids crystallizing directly or from supercooled melts.
Main Results:
- Conformational heterogeneity and interaction degeneracy impede long-range order in ILs.
- Competition among CH3···π and π-mediated interactions creates complex crystallographic landscapes.
- Crystallizing IL cations converge on a consistent effective molecular volume via packing, flexibility, or disorder.
Conclusions:
- Crystallographic disorder in ILs is mechanistically informative, not incidental.
- Disorder reveals how ILs manage volume, interactions, and the liquid-to-crystal transition.
- Understanding IL structural origins is key to controlling their phase behavior.
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