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Donor-Acceptor Properties of a Single-Molecule Altered by On-Surface Complex Formation
Tobias Meier1, Rémy Pawlak1, Shigeki Kawai2,3
1Department of Physics, University of Basel , Klingelbergstr. 82, 4056 Basel, Switzerland.
ACS Nano
|July 22, 2017
Summary
Researchers explored electron donor-acceptor molecules on surfaces. They discovered that forming a complex with a sodium ion alters the molecule's electronic properties, creating a reversible molecular switch.
Area of Science:
- Surface Science
- Molecular Electronics
- Organic Solar Cells
Background:
- Electron donor-acceptor molecules are crucial for molecular electronics and organic solar cells.
- Maintaining their electronic properties upon surface adsorption is vital for device implementation.
Purpose of the Study:
- To investigate the electronic character of a π-conjugated tetrathiafulvalene-fused dipyridophenazine molecule adsorbed on NaCl films on Cu(111).
- To understand the impact of surface adsorption and complex formation on molecular electronic properties.
Main Methods:
- Atomic Force Microscopy (AFM)
- Scanning Tunneling Microscopy (STM)
- On-surface coordination and lateral manipulation
Main Results:
- The molecule exists in either a free or a bound state depending on the adsorption site.
- In the bound state, a chelate complex forms with a Na+ cation, drastically altering charge distribution.
- The intrinsic donor-acceptor character is lost in the complex, but this formation is reversible.
Conclusions:
- Surface coordination with alkali cations can significantly modify molecular electronic properties.
- Reversible chelate complex formation enables tunable donor-acceptor molecular switches.
- This work provides a pathway for designing switchable molecular electronic components.
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