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Switch chemistry at cryogenic conditions: quantum tunnelling under electric fields
Omer Kirshenboim1, Alexander Frenklah1, Sebastian Kozuch1
1Department of Chemistry, Ben-Gurion University of the Negev Beer-Sheva 841051 Israel kozuch@bgu.ac.il.
Chemical Science
|June 24, 2021
Summary
External electric fields (EEF) can control quantum tunnelling (QT) in molecules at near-absolute zero temperatures. This study computationally explores how EEF strength and direction influence QT kinetics, revealing novel reactivity control mechanisms.
Area of Science:
- Computational Chemistry
- Physical Chemistry
- Quantum Mechanics
Background:
- Intramolecular electric fields influence enzyme activity.
- External electric fields (EEF) offer a novel approach to modulate molecular reactivity.
- Quantum tunnelling (QT) is a key mechanism at low temperatures.
Purpose of the Study:
- To computationally investigate the effects of oriented external electric fields (EEF) on molecular reactivity.
- To explore quantum tunnelling (QT) kinetics under EEF influence at near-absolute zero temperatures.
- To examine the impact of EEF on three distinct molecular systems with known QT kinetics.
Main Methods:
- Computational exploration of EEF effects on simple molecules.
- Analysis of QT kinetics in pentalene, semibullvalene, and diazabicyclohexadiene systems.
- Investigation of field strength and directionality on reaction kinetics.
Main Results:
- EEF significantly alters QT kinetics, with effects dependent on field strength and direction.
- Striking results observed for reactions with large dipole changes, like cycloreversion.
- Observed phenomena include inversion of the Arrhenius equation, deactivation of fluxionality, and system stabilization or decomposition.
Conclusions:
- Oriented external electric fields provide a powerful tool to control molecular reactivity via quantum tunnelling.
- EEF can reversibly switch molecular behavior, offering precise control over reaction pathways.
- This research opens new avenues for manipulating chemical reactions at the molecular level.
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