Two dihydroazulene photoswitches … … separated by a meta-phenylene bridge can be opened sequentially to metastable vinylheptafulvene isomers under the influence of light as the intermediate species experiences reduced photoactivity due to a charge-transfer quenching mechanism. Ultimately, both dihydroazulene units are lifted to their high-energy vinylheptafulvene isomers, where the energy is temporarily stored. For more details, see the Full Paper by M. Brøndsted Nielsen et al. on page 3968 ff.
