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Updated: Jul 13, 2026
08:24
Optimization of the Ugi Reaction Using Parallel Synthesis and Automated Liquid Handling
Published on: November 11, 2008
Mediating stochastic switching of single molecules using chemical functionality.
Penelope A Lewis1, Christina E Inman, Yuxing Yao
1Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802-6300, USA.
Journal of the American Chemical Society
|September 30, 2004
Summary
Oligo(phenylene-ethynylene) molecules inserted into amide-containing monolayers exhibit stable ON/OFF switching. This molecular switching is controlled by environmental factors like hydrogen bonding, influenced by the matrix rigidity.
Area of Science:
- Molecular Electronics
- Surface Science
- Organic Chemistry
Background:
- Self-assembled monolayers (SAMs) are crucial for molecular electronics.
- Oligo(phenylene-ethynylene)s (OPEs) are promising molecular switches.
- Amide-containing alkanethiols offer unique matrix properties.
Purpose of the Study:
- To investigate OPE switching in amide-containing alkanethiol SAMs.
- To demonstrate environmental control over molecular switching.
- To understand the role of matrix rigidity in switching behavior.
Main Methods:
- Fabrication of OPE-inserted alkanethiol SAMs.
- Scanning tunneling microscopy (STM) for conductance measurements.
- Analysis of bias-dependent switching and environmental effects.
Main Results:
- OPEs exhibited stable ON and OFF conductance states.
- Bias-dependent switching was observed, driven by hydrogen bonding.
- Fewer switching events occurred compared to previous studies, attributed to matrix rigidity.
Conclusions:
- Amide-containing alkanethiol SAMs provide a stable platform for OPE molecular switches.
- Hydrogen bonding and matrix rigidity significantly influence molecular switching.
- This work advances the design of responsive molecular electronic devices.
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