The optical response of aromatic cyclocarbons

Cyclo[n]carbons are a recently synthesized class of carbon allotropes that offer a unique platform to probe electron delocalization, quantum confinement, and strong correlation effects. Their peculiar electronic properties and bond topologies make them attractive for next-generation molecular optoelectronic, photonic, and quantum technologies. To explore such a potential, a deep understanding of their optical response is necessary. Here, we present the first systematic characterization of the optical response of aromatic cyclo[n]carbons in the whole UV-Vis range, using state-of-the-art many-body methods. Our results show a remarkable tunability of their optical response with respect to ring size and structure, identifying key structure-property relationships. These findings provide a fundamental framework for tailoring the optical properties of π-conjugated carbon nanorings and offer design principles for their integration into adaptive molecular devices and quantum photonics architectures.