Ultrafast Photochromic Reactions of Fulgide Photoswitches

Abstract

ABSTRACT The dynamics of fulgide photoswitches has been investigated applying femtosecond transient absorption spectroscopy. The switching performance of differently substituted fulgides is equally improved in polymer (PMMA) environment as compared to liquid solution (toluene). In the polymer a single pathway for the ring-closure reaction, i.e., without the intermediate observed in toluene, allows for sub-picosecond reaction times. The ring-opening (on-switching) reaction in the donor-acceptor substituted energy-transfer system occurs on ps time scale.