ABSTRACT In this study, solvent‐polarity‐associated photo‐induced processes related to 3‐hydroxy‐2‐(pyridine‐2‐yl)‐4H‐chromen‐4‐one (Py3hc) fluorophore is explored theoretically. Checking the possibility of geometric isomers, we examine the energy barriers for the interconversion among Py3hc‐I, Py3hc‐II, and Py3hc‐III structures in the S 0 state. Only the Py3hc‐III geometry mainly exists in the S 0 state in all solvents. Cause the excited intramolecular proton transfer (ESIPT) plays an important role in this process, we focus on the interaction of intramolecular hydrogen bonding for Py3hc‐III fluorophore. Combining S 1 ‐state hydrogen bonding strengthening with photo‐induced charge redistribution, the tendency of ESIPT reaction could be clearly confirmed for Py3hc fluorophore. The potential curve (PEC) can also be constructed to comprehend the mechanism of the ESIPT process in different polarity solvents, and the transition state can also be searched. The results of this study are expected to provide strategies for designing functional molecules, such as fluorescence switches and other optic‐electronic fields.
Dong et al. (Fri,) studied this question.