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Polymorphism and chiral expression in two-dimensional subphthalocyanine crystals on Au(111)
Nan Jiang1, Yeliang Wang, Qi Liu
1Institute of Physics, Chinese Academy of Sciences, Beijing 100190, PR China.
Physical Chemistry Chemical Physics : PCCP
|February 2, 2010
Summary
Subphthalocyanine (SubPc) adsorption on Au(111) surfaces reveals four distinct phases influenced by coverage and temperature. Spontaneous symmetry breaking and supramolecular chirality are key features observed across these phases.
Area of Science:
- Surface Science
- Supramolecular Chemistry
- Materials Science
Background:
- Subphthalocyanine (SubPc) is a key organic semiconductor molecule.
- Understanding molecular adsorption on metal surfaces is crucial for nanoelectronic device development.
- The Au(111) surface is a well-established model system for surface science studies.
Purpose of the Study:
- To investigate the adsorption behavior of subphthalocyanine (SubPc) on the Au(111) surface.
- To identify and characterize different molecular phases formed during adsorption.
- To understand the influence of coverage and temperature on the self-assembly and structural properties of SubPc.
Main Methods:
- Scanning Tunneling Microscopy (STM) was employed to visualize the molecular arrangements.
- Controlled variation of SubPc coverage and deposition temperature.
Main Results:
- Four distinct adsorption phases of SubPc on Au(111) were identified.
- Two of these phases were observed to coexist under specific conditions.
- Spontaneous symmetry breaking, leading to mirror domains, was a common feature across all observed structures.
- Supramolecular chirality was manifested at various scales within the self-assembled structures.
Conclusions:
- The observed polymorphism in SubPc adsorption is directly linked to variations in coverage and deposition temperature.
- STM provides detailed insights into the origin and nature of these different molecular phases.
- The study highlights the complex self-assembly behavior and chiral expression of SubPc on metal surfaces.
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