From starphenes to non-benzenoid linear conjugated polymers by substrate templating

Area of Science:

• Surface chemistry
• Materials science
• Nanotechnology

Background:

• On-surface synthesis enables the creation and study of novel molecular architectures.
• Scanning tunneling microscopy (STM) provides atomic-level characterization of materials.
• Controlling molecular reactivity on surfaces is key to designing new functional materials.

Purpose of the Study:

• To demonstrate control over the reactivity of an anthracene-based precursor on different gold surfaces.
• To synthesize and characterize novel nanostructures, specifically starphene derivatives and conjugated polymers.
• To investigate the electronic properties of the synthesized molecular structures.

Main Methods:

• On-surface synthesis using an anthracene-based precursor.
• Characterization using scanning tunneling microscopy (STM).
• Surface symmetry manipulation (Au(111) vs. Au(110)).
• Electronic property assessment via tunneling spectroscopy and DFT calculations.

Main Results:

• Selective formation of a starphene derivative on the three-fold symmetric Au(111) surface.
• Selective growth of non-benzenoid linear conjugated polymers on the two-fold symmetric Au(110) surface.
• Detailed electronic properties of both product structures were determined.

Conclusions:

• Surface symmetry is a critical factor in directing on-surface chemical reactions.
• This approach enables the targeted synthesis of complex molecular nanostructures.
• Advances the understanding and potential applications of starphenes and conjugated polymers.