Activating charge-transfer state formation in strongly-coupled dimers using DNA scaffolds

Area of Science:

• Supramolecular Chemistry
• Materials Science
• Photochemistry

Background:

• Multichromophoric assemblies are crucial for energy processes in natural and synthetic systems.
• Precise chromophore placement is key to programming material functionalities.
• DNA nanomaterials offer a programmable scaffold for controlling excitonic properties.

Purpose of the Study:

• To demonstrate control over photochemical processes, specifically interchromophore charge transfer, using DNA scaffolds.
• To engineer DNA-chromophore platforms allowing tailored long-range excitonic and short-range charge-transfer couplings.
• To explore the potential of DNA-guided geometric control for accessing novel photochemical processes.

Main Methods:

• Utilized DNA nanomaterials as a scaffold for precise chromophore placement.
• Employed combinatorial screening to discover chromophore geometries influencing photochemistry.
• Combined spectroscopic and computational analyses to investigate charge-transfer dynamics.

Main Results:

• Established a DNA-chromophore platform for tailoring excitonic and charge-transfer couplings.
• Discovered chromophore geometries that can enhance or suppress photochemical reactions.
• Confirmed the presence of symmetry-breaking charge transfer in DNA-scaffolded squaraines, a novel achievement for these chromophores.

Conclusions:

• DNA-guided geometric control enables access to previously unattainable photochemical processes.
• The platform facilitates programming the evolution of excitonic states in molecular chromophores.
• Opens new avenues for designing advanced photoactive materials for applications in light harvesting and computation.