Chiral symmetry breaking in two-dimensional C60-ACA intermixed systems.

Area of Science:

• Surface Science
• Supramolecular Chemistry
• Materials Science

Background:

• Controlling the self-assembly of molecular overlayers is crucial for designing advanced materials.
• Fullerene (C60) packing and chirality are key properties influencing their electronic and optical behavior.
• Achieving precise structural control in molecular assemblies remains a significant challenge.

Purpose of the Study:

• To demonstrate a new method for fabricating C60 overlayers with controlled spacing and chirality.
• To investigate the role of coadsorption with acridine-9-carboxylic acid (ACA) in directing C60 assembly.
• To achieve enantiopure C60 domains with significantly altered periodicity.

Main Methods:

• Fabrication of C60 overlayers via reactive coadsorption with acridine-9-carboxylic acid (ACA).
• Utilizing mismatched symmetries of coadsorbates and specific intermolecular/adsorbate-substrate interactions for structural control.
• Characterization of the resulting supramolecular structure and its chiral properties.

Main Results:

• Successful fabrication of C60 overlayers with controlled spacing and chirality.
• The supramolecular structure exhibits a C60 period nearly three times larger than the standard 1 nm packing.
• The resulting assembly exists in enantiopure domains, demonstrating robust chirality.

Conclusions:

• Reactive coadsorption with ACA provides an effective strategy for controlling C60 overlayer structure.
• Mismatched symmetries and specific interactions are key to achieving large C60 spacing and chirality.
• This method opens new avenues for designing chiral fullerene-based materials and supramolecular systems.