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Updated: May 4, 2026
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Dissolution Dynamic Nuclear Polarization Instrumentation for Real-time Enzymatic Reaction Rate Measurements by NMR
Published on: February 23, 2016
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The non-ergodic nature of internal conversion
Theis I Sølling1, Thomas S Kuhlman, Anne B Stephansen
1Maersk Oil Research and Technology Centre, TECH 2 Building, Level 1, Unit 107, Al Gharrafa Street, Al Rayyan, Education City, PO Box 210112, Doha (Qatar). theis.solling@maerskoil.com.
Summary
Molecules exhibit non-ergodic internal conversion, where nuclear dynamics sample limited phase space, localizing energy and enabling ultrafast excited-state deactivation. This nonstatistical process is crucial for chemical reactions and biomolecular stability.
Area of Science:
- Physical Chemistry
- Chemical Physics
- Molecular Dynamics
Background:
- Light absorption induces ultrafast molecular dynamics, coupling electronic and nuclear motion.
- Potential energy surfaces are critical for guiding nuclear motion in chemical reactions.
- Internal conversion describes the non-radiative transition between electronic states.
Purpose of the Study:
- To review the non-ergodic nature of internal conversion.
- To highlight the nonstatistical aspects of excited-state deactivation processes.
- To explore how nonstatistical internal conversion contributes to biomolecular stability.
Main Methods:
- Review of theoretical concepts in molecular dynamics.
- Analysis of experimental results demonstrating nonstatistical behavior.
- Categorization of examples into four distinct groups.
Main Results:
- Non-ergodic dynamics lead to energy localization in specific degrees of freedom or reactive modes.
- Excited-state deactivation can be ultrafast due to nonstatistical sampling of phase space.
- Nonstatistical internal conversion is observed in DNA and disulfide bonds, contributing to biomolecular stability.
Conclusions:
- Nonstatistical internal conversion is a key mechanism for ultrafast excited-state deactivation.
- This process allows molecules to efficiently dissipate energy, preventing unwanted reactions.
- Understanding non-ergodic dynamics is essential for controlling chemical reactions and designing stable biomolecules.
Keywords:
electronic structureenergy localizationinternal conversionmolecular dynamicspotential energy surfacesMore Related Videos
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