Spectroscopic signatures of short- and long-range excitonic interactions in organic photovoltaic materials

A large class of organic chromophores form self-assembled aggregates consisting up to 10^5 molecules on micron scale. Their exotic photophysical properties imply interesting chemical physics principles and promise useful optoelectronic applications. However, the microscopic details of these supramolecular structures as well as those of the excitonic interactions among constituent chromophores, critically responsible for the said exotic photophysics, continue to evade conclusive and systematic characterization even nearly a century after their discovery. In this talk I will cover the fundamental challenges and some of the theoretical insights obtained in our ongoing effort in studying these systems, primarily in identifying key inter-relationships between spectroscopic signatures and structural parameters. Prospects in applying and generalizing these principles to related systems will be discussed.

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[5] 10.26434/chemrxiv-2022-5m8sx