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Updated: Jun 25, 2026
08:40
Light-driven Molecular Motors on Surfaces for Single Molecular Imaging
Published on: March 13, 2019
A quantitative single-molecule study of thioether molecular rotors
Ashleigh E Baber1, Heather L Tierney, E Charles H Sykes
1Department of Chemistry, Tufts University, Medford, Massachusetts 02155-5813, USA.
ACS Nano
|February 12, 2009
Summary
This study reveals how thioethers rotate on gold surfaces, identifying the CH(2) group
Area of Science:
- Surface Science and Molecular Dynamics
- Physical Chemistry of Nanomaterials
Background:
- Thioethers offer a simple model system for studying molecular motion.
- Understanding molecular rotation is crucial for nanoscale device development.
Purpose of the Study:
- To investigate the fundamental, single-molecule rotation of thioethers on gold surfaces.
- To quantify the energetic barrier and kinetic parameters governing thioether molecular motion.
- To explore mechanical control over molecular rotation at the single-molecule level.
Main Methods:
- Utilized low-temperature scanning tunneling microscopy (STM) for real-time observation.
- Performed single-molecule manipulation experiments to control molecular interactions.
- Analyzed molecular rotation as a function of temperature and molecular proximity.
Main Results:
- Quantified the energetic barrier and pre-exponential factor for thioether rotation.
- Identified the movement of the second CH(2) group as the primary source of the rotational barrier.
- Demonstrated reversible switching of molecular rotation via single-molecule manipulation.
Conclusions:
- The thioether backbone serves as an effective platform for single-molecule rotation studies.
- The torsional barrier to rotation for dibutyl sulfide was determined to be approximately 1.2 kJ/mol.
- Molecular rotation dynamics can be precisely controlled and studied at the single-molecule level.
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