Understanding the structure–property relationships in polycyclic conjugated hydrocarbons (PCHs) is crucial for controlling their electronic properties and developing new optical function materials. Aromaticity is a fundamentally important and intriguing property of numerous organic chemical structures and has stimulated a myriad of experimental and theoretical investigations. Exploiting aromaticity rules for the rational design of optoelectronic materials with the desired photophysical characteristics is a challenging yet fascinating task. Herein we present an in-depth computational and spectroscopic study on the structure–property relationships of dinaphthopentalenes (DNPs). Results highlight that the different fusion patterns between 4n π and 4n+2 π units endow these polycyclic conjugated hydrocarbons (PCHs) with the tunable aromaticity in the ground state/excited state, which leads to the diverse electronic structures and consequently the distinctive excited state photophysics. Accordingly, we propose a combined aromaticity design strategy for rationally modulating and tailoring electronic and optical properties of PCH skeletons. These outcomes not only present a full picture of the excited state dynamics of the DNP system and afford a new class of efficient singlet fission-active materials but also provide some basic guidelines for exploiting aromaticity rules to design and develop new optical function materials.

https://www.chinesechemsoc.org/doi/10.31635/ccschem.022.202202430