<i>Ab initio</i> insights into the mechanism of excited-state intramolecular proton transfer triggered by the second excited singlet state of a fluorescent dye: an anti-Kasha behavior

Abstract

An excited-state intramolecular proton transfer (ESIPT) reaction triggered by the second excited singlet S₂ state is found by <italic>ab initio</italic> calculations to be an ultrafast process for a novel fluorophore.