Excitation wavelength-dependent fluorescence anisotropy of 3-hydroxyflavone: revisiting the solvation processes and high-energy state excitation in ESIPT-active compounds

Abstract

The fluorescence anisotropy of 3HF normal form changes abruptly with decreasing excitation wavelength. This phenomenon can be explained by breaking of solute–solvent hydrogen bonds and excitation of ESIPT-active fluorophores to high-energy states.