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Updated: Aug 5, 2026
11:04
Synthesis of Ionic Liquid Based Electrolytes, Assembly of Li-ion Batteries, and Measurements of Performance at High Temperature
Published on: December 20, 2016
Room temperature ionic liquids and deep eutectic solvents: distinct classes or a continuum of liquid matter?
1Departamento de Bioquímica y Biología Molecular B e Inmunología Facultad de Química, Universidad de Murcia, P.O. Box 4021, E-30100 Murcia, Spain. j.dupont@um.es.
Chemical Communications (Cambridge, England)
|July 31, 2026
Summary
Molten salts, room-temperature ionic liquids (RTILs), and deep eutectic solvents (DESs) represent a continuous spectrum of dynamic liquid phases. A unified framework is proposed, viewing them as interconnected ionic, molecular, and ionic-molecular fluids.
Area of Science:
- Condensed matter physics and physical chemistry.
- Materials science and chemical engineering.
Background:
- Historically, low-melting solids like molten salts, RTILs, and DESs were classified by composition or properties.
- Emerging evidence suggests these materials are dynamic condensed phases with cooperative interactions.
Purpose of the Study:
- To propose a unified framework for understanding and classifying ionic, molecular, and ionic-molecular fluids.
- To challenge traditional distinctions between molten salts, RTILs, and DESs.
Main Methods:
- Review of historical development in the field.
- Analysis of experimental and theoretical evidence on cooperative interactions.
- Revisiting classifications from fused salts to modern ILs and DESs.
Main Results:
- Molten salts, RTILs, and DESs exist on a continuous landscape of liquid matter.
- Intermolecular forces (Coulombic, hydrogen bonding, etc.) and supramolecular organization are key.
- The balance between ionicity, molecular association, and supramolecular structure dictates properties.
Conclusions:
- A unified framework is proposed, integrating molten salts, RTILs, and DESs.
- Traditional classifications based on distinct classes are insufficient.
- Understanding liquid matter requires considering the continuum of ionic, molecular, and mixed systems.
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