Transient absorption spectroscopy: a mechanistic tool for triplet sensitizers and their applications

. These events are fundamental steps for the mechanisms of many chemical processes including organic synthetic reactions, photo-polymerization, photodynamic therapy, and thermally activated delayed fluorescence. In this review we thoroughly discuss and critically analyze how to exploit TAS to derive mechanistic insights in these processes. Moreover, some basic principles that can help in easily elucidating and predicting a transient absorption (TA) spectrum are included with previously reported examples. This paper is aimed at facilitating the application of TAS as a tool for mechanistic studies and to provide an overview of the techniques related to scientists and students with diverse scientific backgrounds.