RT Journal Article T1 E/Z Molecular Photoswitches Activated by Two-Photon Absorption: Comparison between Different Families A1 Marazzi, Marco A1 Garcia-Iriepa, Cristina A1 Benitez-Martin, Carlos A1 Najera, Francisco A1 Monari, Antonio A1 Sampedro, Diego K1 E K1 Z photoswitches K1 photoisomerization K1 two-photon absorption K1 Azobenzene photoswitches K1 One-photon K1 Photochemical characterization K1 Photoisomerization dynamics K1 Benzylidene-oxazolones K1 Caged compounds K1 Quantum yield K1 Light K1 Switches K1 Chromophores AB Nonlinear optical techniques as two-photon absorption (TPA) have raised relevant interest within the last years due to the capability to excite chromophores with photons of wavelength equal to only half of the corresponding one-photon absorption energy. At the same time, its probability being proportional to the square of the light source intensity, it allows a better spatial control of the light-induced phenomenon. Although a consistent number of experimental studies focus on increasing the TPA cross section, very few of them are devoted to the study of photochemical phenomena induced by TPA. Here, we show a design strategy to find suitable E/Z photoswitches that can be activated by TPA. A theoretical approach is followed to predict the TPA cross sections related to different excited states of various photoswitches' families, finally concluding that protonated Schiff-bases (retinal)-like photoswitches outperform compared to the others. The donor-acceptor substitution effect is therefore rationalized for the successful TPA activatable photoswitch, in order to maximize its properties, finally also forecasting a possible application in optogenetics. Some experimental measurements are also carried out to support our conclusions. PB Mdpi YR 2021 FD 2021-12-01 LK https://hdl.handle.net/10668/25311 UL https://hdl.handle.net/10668/25311 LA en DS RISalud RD Apr 10, 2025