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A van der Waals Model of Solvation Thermodynamics
Attila Tortorella1,2, Giuseppe Graziano3
1Scuola Superiore Meridionale, Via Mezzocannone, 4, 80138 Naples, Italy.
Entropy (Basel, Switzerland)
|August 29, 2024
Summary
The van der Waals model provides analytical formulas for solvation thermodynamics. It explains free energy and entropy changes during solute transfer, aligning with experimental data.
Area of Science:
- Physical Chemistry
- Thermodynamics
- Statistical Mechanics
Background:
- Solvation is crucial for chemical reactions and biological processes.
- Understanding solvation thermodynamics aids in predicting molecular behavior in liquids.
Purpose of the Study:
- To derive analytical formulas for solvation thermodynamic functions using the van der Waals model.
- To elucidate the contributions to solvation Gibbs free energy and entropy changes.
Main Methods:
- Application of the van der Waals model for liquids.
- Derivation of analytical expressions for thermodynamic functions.
- Analysis of cavity formation and intermolecular interactions.
Main Results:
- Solvation Gibbs free energy comprises cavity creation costs and attraction gains.
- Solvation entropy involves entropy loss from restricted liquid mobility and entropy gain from structural reorganization.
- The derived model shows qualitative agreement with experimental observations.
Conclusions:
- The van der Waals model offers a theoretical framework for understanding solvation.
- The model successfully separates and quantifies key contributions to solvation thermodynamics.
- Further validation with experimental data is supported by the model's qualitative agreement.
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