1- In fluorescence, the emission light is of longer wavelength than the excitation light (Stokes shift). What is the inner-filter (quenching) effect?
1- In fluorescence, the emission light is of longer wavelength than the excitation light (Stokes shift). What is the inner-filter (quenching) effect?
Because some of that energy was already released as non-radiative transition and thermal energy, the energy of the now fluorescing photon is lower than the energy of the excitation photon. Thus, the energy released during fluorescence will always be of a longer wavelength than that needed for excitation.
Quenching is loss of fluorescence due to transfer of energy to the solvent or other solutes
