Escape rate of a charge carrier from a semiconducting polymer chain
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View abstract on PubMed
Summary
This summary is machine-generated.Charge carriers in semiconducting polymers move along chains and hop between them. This study provides a new formula for inter-chain hopping, crucial for designing better polymers.
Area Of Science
- Materials Science
- Polymer Chemistry
- Organic Electronics
Background
- Charge transport in amorphous semiconducting polymers is vital for electronic devices.
- Inter-chain hopping is a key factor influencing charge carrier mobility.
- Understanding escape time is critical for polymer design and performance optimization.
Purpose Of The Study
- To derive a general expression for the inter-chain hopping escape rate in semiconducting polymers.
- To simplify this expression in the limit of vanishing reorganization energy.
- To investigate the sensitivity of the escape rate to disorder and temperature.
Main Methods
- Development of a general theoretical expression for the escape rate.
- Analysis in the limit of vanishing reorganization energy.
- Derivation of necessary parameters using classical and quantum chemical models.
- Illustration using two realistic semiconducting polymer examples.
Main Results
- A general expression for the inter-chain escape rate was derived.
- A simplified expression was obtained for vanishing reorganization energy.
- The escape rate is more sensitive to disorder and temperature than intra-chain transport.
- Parameters for rate evaluation were shown to be derivable from existing models.
Conclusions
- The derived escape rate expression offers insights into charge transport in semiconducting polymers.
- Inter-chain hopping is significantly influenced by disorder and temperature.
- The methodology allows for the characterization of realistic polymeric materials for improved device design.
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