Merocyanine and Spiropyran Adsorption on Graphene

Area of Science:

• Materials Science
• Computational Chemistry
• Surface Science

Background:

• Spiropyran-based molecules are light-sensitive switches with potential applications in advanced materials.
• Understanding their surface adsorption is key to controlling their behavior and enabling film growth.

Purpose of the Study:

• To investigate the adsorption of spiropyran molecular switches and their isomers on graphene.
• To analyze the influence of molecular structure on adsorption and dimer formation.
• To elucidate the mechanisms governing self-assembly for potential film growth.

Main Methods:

• Utilized a combination of quantum-chemical calculations.
• Employed force-field-based simulations.
• Studied four distinct spiropyran molecules and their merocyanine isomers.

Main Results:

• Identified the significant role of end groups in surface adsorption and intermolecular configurations.
• Revealed that van der Waals interactions and electrostatic forces drive adsorption and dimer formation.
• Characterized dimer formation as a precursor to substrate-wide film growth.
• Discovered various dimer configurations based on different merocyanine conformers.

Conclusions:

• The adsorption and self-assembly of spiropyran switches on graphene are governed by molecular structure and non-covalent interactions.
• These findings provide fundamental insights into controlling molecular switch behavior on surfaces.
• The study lays the groundwork for designing and fabricating molecular films with tailored properties.