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Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone
Published on: February 23, 2017
Switching in molecular transport junctions: polarization response
Sina Yeganeh1, Michael Galperin, Mark A Ratner
1Department of Chemistry, Center for Nanofabrication and Molecular Self Assembly, Northwestern University, Evanston, Illinois 60208-3113, USA.
Journal of the American Chemical Society
|October 6, 2007
Summary
Researchers explored molecular junctions, explaining switching and negative differential resistance (NDR) using a polaron model. This model, enhanced with electronic structure calculations, successfully predicts NDR behavior in molecular systems.
Area of Science:
- Molecular electronics
- Condensed matter physics
- Computational chemistry
Background:
- Molecular junctions exhibit complex electrical behaviors, including switching and negative differential resistance (NDR).
- Understanding the underlying mechanisms is crucial for developing novel electronic devices.
Purpose of the Study:
- To investigate and explain the switching and NDR phenomena in molecular junctions.
- To refine theoretical models for predicting these behaviors.
Main Methods:
- Discussion of various theoretical models for molecular junction behavior.
- Electronic structure calculations for substituted oligo(phenylene ethynylene) molecules.
- Elaboration of a polaron model with image charge effects and computational parameters.
Main Results:
- A previously proposed polaron model was found to successfully predict NDR behavior.
- The elaborated polaron model incorporates substituent effects, conformational changes, charging, and image charge stabilization.
Conclusions:
- The refined polaron model provides a robust framework for understanding NDR in molecular junctions.
- This work advances the predictive capability of theoretical models in molecular electronics.
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