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Updated: Jun 27, 2025
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Quantitative predictive theories through integrating quantum, statistical, equilibrium, and nonequilibrium
1Department of Materials Science and Engineering, The Pennsylvania State University, University Park, PA 16802, United States of America.
Summary
A new zentropy theory integrates quantum mechanics and statistical mechanics to accurately predict system properties. This approach also extends to nonequilibrium systems, offering quantitative predictions across all scales.
Area of Science:
- Thermodynamics
- Quantum Mechanics
- Statistical Mechanics
Background:
- Current thermodynamics relies on separate theories for equilibrium (Gibbs) and nonequilibrium (Onsager) systems.
- Density functional theory (DFT) quantifies quantum mechanics but remains separate from thermodynamics.
- Existing models lack quantitative agreement with experimental observations due to their isolated nature.
Purpose of the Study:
- To develop a unified theoretical framework for predicting thermodynamic properties of complex systems.
- To bridge the gap between quantum mechanics, statistical mechanics, and nonequilibrium thermodynamics.
- To provide quantitative predictive theories across electronic to observable scales.
Main Methods:
- Development of a multiscale entropy approach, termed zentropy theory.
- Integration of Density Functional Theory (DFT) with Gibbs statistical mechanics.
- Incorporation of Hillert's combined law for nonequilibrium systems to develop the theory of cross phenomena.
Main Results:
- Zentropy theory accurately predicts entropy and free energy for complex systems.
- The theory of cross phenomena extends beyond the Onsager Theorem for nonequilibrium systems.
- A unified framework provides quantitative predictions from electronic to macroscopic scales.
Conclusions:
- The integrated zentropy theory and theory of cross phenomena offer a comprehensive approach to thermodynamics.
- This unified theory addresses limitations of separate models, improving predictive accuracy.
- The work provides a foundation for quantitative predictions in diverse scientific domains.
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