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Preparation of Binary and Ternary Deep Eutectic Systems
Published on: October 31, 2019
Energy landscape view of nonideality in binary mixtures
Sneha Elizabeth Abraham1, Dwaipayan Chakrabarti, Biman Bagchi
1Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560 012, India.
The Journal of Chemical Physics
|March 3, 2007
Summary
This study explores the energy landscape of binary mixtures to understand viscosity deviations from Raoult
Area of Science:
- Physical Chemistry
- Chemical Engineering
- Materials Science
Background:
- Deviations from Raoult's Law in binary mixtures are often attributed to structure formation or breakage.
- A detailed theoretical framework for these concepts in mixture nonideality is lacking.
- Understanding these deviations is crucial for predicting and controlling mixture properties.
Purpose of the Study:
- To present an energy landscape perspective on the nonideality of binary mixture viscosity.
- To theoretically model the roles of structure formers and structure breakers in mixture viscosity.
- To correlate inherent structure energy and configurational entropy with viscosity.
Main Methods:
- Utilized two distinct theoretical models representing structure-forming and structure-breaking components.
- Analyzed the average inherent structure energy and its relationship with viscosity.
- Computed the configurational entropy of the liquid parent phase for both model systems.
Main Results:
- A consistent inverse correlation was observed between average inherent structure energy and viscosity for both models.
- Structure formers exhibited enhanced short-range order due to strong attractive interactions.
- Structure breakers showed weaker interactions, leading to no significant short-range order enhancement and occasional phase separation.
- Configurational entropy also demonstrated an inverse correlation with viscosity in both investigated systems.
Conclusions:
- The energy landscape approach provides a theoretical basis for understanding nonideality in binary mixture viscosity.
- Structure formation and breakage significantly influence mixture viscosity through changes in molecular ordering and interactions.
- Both inherent structure energy and configurational entropy are valuable indicators of viscosity in binary mixtures.
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