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Updated: Apr 28, 2026
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Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
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Quinacridone on Ag(111): Hydrogen Bonding versus Chirality
Thorsten Wagner1, Michael Györök1, Daniel Huber1
1Institute of Experimental Physics, Johannes Kepler University Linz , Altenberger Str. 69, 4040 Linz, Austria.
Summary
Quinacridone molecules form ordered rows on surfaces, driven by hydrogen bonds and molecular chirality. Annealing transforms these into stacked dimers, revealing competing structural influences.
Area of Science:
- Materials Science
- Surface Science
- Organic Electronics
Background:
- Quinacridone (QA) exhibits high performance in organic electronics.
- Hydrogen bonds influence structural order in QA.
- Surface adsorption introduces 2D-chirality effects.
Purpose of the Study:
- Investigate the self-assembly of quinacridone on Ag(111).
- Understand the role of hydrogen bonding and chirality in QA surface structures.
- Characterize structural changes upon annealing.
Main Methods:
- Scanning Tunneling Microscopy (STM) for molecular imaging.
- Low-Energy Electron Diffraction (LEED) for structural analysis.
- Photoelectron Emission Microscopy (PEEM) for surface characterization.
Main Results:
- Monolayer QA forms quasi-1D rows of parallel, single-handedness molecules linked by hydrogen bonds at room temperature.
- Annealing to 550-570 K induces a structural transition.
- The annealed structure consists of stacked heterochiral quinacridone dimers with altered intermolecular arrangements.
Conclusions:
- Hydrogen bonding and 2D-chirality compete, dictating quinacridone's surface structures.
- Annealing leads to distinct, thermodynamically stable supramolecular arrangements.
- Understanding these interactions is key for designing high-performance organic devices.
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