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Information Theoretical Approach to Coupled Electron-Nuclear Wave Packet Dynamics: Time-Dependent Differential
Peter Schürger1, Volker Engel1
1Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Emil-Fischer-Str. 42, 97074 Würzburg, Germany.
The Journal of Physical Chemistry Letters
|January 6, 2023
Summary
We analyzed quantum particle behavior using differential Shannon entropies. This reveals how electron-nuclear interactions and localization change over time, especially during non-adiabatic coupling.
Area of Science:
- Quantum chemistry
- Theoretical physics
- Chemical physics
Background:
- Differential Shannon entropy quantifies particle delocalization in quantum systems.
- Electron-nuclear coupling influences quantum dynamics and particle localization.
- Born-Oppenheimer approximation separates electronic and nuclear motion.
Purpose of the Study:
- Investigate differential Shannon entropies in coupled electron-nuclear systems.
- Understand information gained about particle localization and correlation.
- Analyze entropy dynamics under different coupling regimes.
Main Methods:
- Calculating position-space quantum probability densities.
- Computing electronic and nuclear differential Shannon entropies.
- Decomposing entropy contributions from electronic states.
Main Results:
- Entropy reveals particle localization and electron-nuclear correlation.
- Correlation decreases when wave packets reach classical turning points.
- Strong non-adiabatic coupling leads to constant electronic entropy and loss of correlation.
Conclusions:
- Time-dependent entropy reflects nuclear information alone during strong non-adiabatic coupling.
- Entropy decomposition provides insight into state-specific populations and nuclear wave packet localization.
- Shannon entropy is a valuable tool for analyzing quantum system dynamics.
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