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Updated: Nov 7, 2025
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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Resultant Information Descriptors, Equilibrium States and Ensemble Entropy †
1Department of Theoretical Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Cracow, Poland.
Entropy (Basel, Switzerland)
|April 30, 2021
Summary
This study reexamines information content in electronic states, emphasizing entropy combining probability and phase densities. New insights reveal nonclassical contributions and equivalent reactivity descriptors for chemical processes.
Area of Science:
- Quantum Chemistry
- Chemical Physics
- Information Theory
Background:
- Electronic states contain information derived from probability and phase densities.
- Classical information measures (Shannon entropy, Fisher information) capture probability distributions.
- Nonclassical information contributions arise from phase components and probability convection.
Purpose of the Study:
- To reexamine sources of information in electronic states.
- To emphasize the need for resultant measures of entropy/information content.
- To establish the equivalence of energy and gradient information descriptors for chemical processes.
Main Methods:
- Reexamination of continuity relations for wavefunction modulus and phase.
- Application of the local-energy concept to phase equalization.
- Analysis of latent probability currents in equilibrium quantum states.
- Utilizing grand-ensemble description for reactivity criteria.
Main Results:
- Identified classical contributions from probability distributions and nonclassical contributions from phase components.
- Related latent probability currents to horizontal ('thermodynamic') phase.
- Demonstrated equivalence between energy and resultant gradient information (kinetic energy) descriptors.
- Showed entropic analogs of reactivity criteria provide equivalent indices for charge transfer.
Conclusions:
- A comprehensive measure of information content in electronic states is crucial.
- Phase information plays a significant role in nonclassical contributions.
- Gradient information descriptors offer an equivalent and valuable perspective on chemical reactivity and charge transfer phenomena.
Keywords:
continuity relationsgrand ensembleinformation sourcesphase equalizationreactivity criteriaresultant informationMore Related Videos
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