Interestingly, Saito et al. researched π-expanded oxepins structures with heptaromatic rings with 8π electron configurations (Figure ). By expanding the molecule with increasing benzene rings to alter the conjugation distribution, the inhibition of vibration at low temperatures leads to enhanced emission in the molecules (Figure and). Notably, oxepins with a single expanded benzene ring did not demonstrate changes in viscosity response in DMSO/glycerol solvents. Authors speculate that this apparent viscosity independence of miniscale molecule can be attributed to the very fast planarization dynamics with a barrierless S1 energy profile, as well as some void regions that remain near the flapping wings (benzene and naphthalene moieties).