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Updated: May 11, 2026
09:22
Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Structural polymorphism in self-assembled networks of a triphenylene based macrocycle
Kunal S Mali1, Matthias Georg Schwab, Xinliang Feng
1Division of Molecular Imaging and Photonics, Department of Chemistry, KU Leuven-University of Leuven, Leuven, Belgium.
Physical Chemistry Chemical Physics : PCCP
|May 18, 2013
Summary
Controlling molecular self-assembly is key for functional materials. This study shows concentration dictates the 2D structure of macrocycles, transitioning from linear to porous networks.
Area of Science:
- Materials Science
- Supramolecular Chemistry
- Surface Science
Background:
- Controlling structural polymorphism in self-assembled networks is crucial for functional molecules.
- Self-assembled monolayers (SAMs) offer a platform for ordered molecular structures.
- Discotic macrocycles are promising organic semiconductors.
Purpose of the Study:
- To investigate the concentration-controlled structural evolution in self-assembled monolayers (SAMs) of a large triangular discotic macrocycle.
- To understand the 2D phase behavior at the liquid-solid interface.
- To provide guidelines for controlling thin film morphology.
Main Methods:
- Scanning tunneling microscopy (STM) was used to observe adlayer structures.
- Experiments were conducted at the 1,2,4-trichlorobenzene/highly oriented pyrolytic graphite (HOPG) interface.
- Time-dependent STM imaging monitored structural transformations.
Main Results:
- Adlayers exhibited concentration-dependent 2D phase behavior.
- High concentrations favored high-density linear packing.
- Lower concentrations resulted in low-density porous patterns, with a trimeric hexagonal phase at intermediate concentrations.
- Solvent choice significantly impacted self-assembly, leading to amorphous networks.
Conclusions:
- The study reveals concentration-driven polymorphism in discotic macrocycle SAMs.
- Structural evolution from linear to porous networks was demonstrated.
- Insights into controlling organic semiconductor thin film morphology were provided.
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