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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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Understanding Periodic Dislocations in 2D Supramolecular Crystals: The PFP/Ag(111) Interface
E Goiri1, J M García-Lastra2, M Corso1
1†Donostia International Physics Center, Paseo Manuel Lardizabal 4, E-20018 Donostia-San Sebastián, Spain.
The Journal of Physical Chemistry Letters
|August 20, 2015
Summary
Dislocations in molecular films relieve strain, primarily driven by optimizing molecule-substrate interactions. This allows a temperature-induced shift from strained patterns to incommensurate moiré structures.
Area of Science:
- Materials Science
- Surface Science
- Supramolecular Chemistry
Background:
- In-plane dislocation networks form in films to relieve elastic strain at interfaces.
- Understanding dislocation drivers in organic films is complex due to weak supramolecular and molecule-substrate interactions.
Purpose of the Study:
- To investigate the primary driving force behind nanoscale dislocation patterns in molecular films.
- To elucidate the interplay between supramolecular and molecule-substrate interactions in organic thin films.
Main Methods:
- Combined experimental and theoretical approaches were employed.
- Analysis of periodic dislocations in a molecular perfluorophenyl (PFP) film.
Main Results:
- Periodic dislocations in the PFP film are predominantly driven by optimized molecule-substrate interactions.
- The energy imbalance in organic networks is lower than in inorganic films.
- A thermally induced transition from strain-driven dislocations to incommensurate moiré patterns was observed.
Conclusions:
- Molecule-substrate interactions are the main drivers of dislocations in molecular PFP films.
- Organic dislocation networks exhibit lower energy barriers, enabling thermally driven phase transitions.
- This work clarifies the mechanisms governing nanoscale patterns in organic thin films.
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