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Charge-transport-induced dissociation in donor-bridge-acceptor complexes
1Schulich Faculty of Chemistry and The Lise Meitner Center for Computational Quantum Chemistry, Technion-Israel Institute of Technology, Haifa 32000, Israel.
The Journal of Chemical Physics
|January 7, 2009
Summary
This study explores two charge-transport-induced dissociation mechanisms in molecular complexes. Researchers identified direct and resonance-mediated pathways, suggesting conditions for experimental observation.
Area of Science:
- Physical Chemistry
- Chemical Physics
- Molecular Dynamics
Background:
- Understanding charge transport is crucial for molecular electronics.
- Dissociation in donor-bridge-acceptor systems impacts device performance.
- Nonlinear coupling effects in molecular vibrations are complex.
Purpose of the Study:
- To investigate mechanisms of charge-transport-induced dissociation.
- To model dissociation pathways in anharmonic molecular bridges.
- To analyze the interplay between different dissociation mechanisms.
Main Methods:
- Developed a simplified model coupling anharmonic bridge vibrations to electronic degrees of freedom.
- Analyzed direct dissociation via vibronic excitations.
- Investigated dissociation involving Feshbach resonances (quasibound vibrational states).
Main Results:
- Identified two distinct charge-transport-induced dissociation mechanisms.
- Characterized a direct mechanism involving nuclear continuum excitations.
- Revealed an alternative mechanism through intermediate quasibound vibrational states.
- Examined the dependence of these mechanisms on system parameters.
Conclusions:
- The study provides a theoretical framework for understanding charge-transport-induced dissociation.
- Two key mechanisms, direct and resonance-mediated, were elucidated.
- A parameter regime for potential experimental observation of these phenomena was proposed.
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