Fig. 1.

Design and absorption of ITI. a The structure of Iminothioindoxyl (ITI) is a hybrid of thioindigo (purple) and azobenzene (orange). The R group indicates various substituents to study the electronic effects on the photochemical properties. b Absorption spectra of 40 μM ITI 1a in cyclohexane, toluene, chloroform, MeOH and DMSO. c Millisecond transient absorption of 400 μM ITI 1a in MeOH at room temperature. The sample was irradiated with a 430 nm light pulse, upon which the spectrum was recorded with 1 ms delay steps. The color bar represents increased delay of transient absorption spectroscopy and the purple line represents the spectrum of 40 μM of Z-ITI 1a in MeOH after thermal equilibration