Photochemistry has been developed as a powerful tool for organic transformations, such photoredox catalysis, photocycloaddition, and photoisomerization. Traditional photochemistry relies on molecular photosensitizers. Recently in Chem Catalysis, Weiss colleagues applied semiconductor nanoparticles photosensitizers to drive [2 + 2] cycloaddition of aryl-conjugated dienes with high chemo- ...

A review of literature on photoisomerization of bilirubin and photoactive yellow protein suggests possible involvement of the volume-conserving Hula-twist (HT) reaction mechanism in their primary photochemical processes. Additional definitive experiments to verify their involvement are proposed. Information related to photoproducts of bacteriorhodopsin, rhodopsin, and phytochrome are reviewed. ...

(E)-Azobenzene is introduced as a suitable chemical actinometer in the visible spectral range (440–540 nm) for photon flux determination of fluidic microphotoreactors or assessing efficiency light photo-induced reactions, its evaluation straightforward without tedious analytics. Photoisomerization quantum yields (ΦE→Z) (E)-azobenzene were accurately determined upon irradiation at several wavele...