Kasha 1950: emission occurs from lowest excited state of given multiplicity (S1 fluorescence, T1 phosphorescence) regardless of excitation wavelength; explains independence of fluorescence spectrum from lambda_ex.
Kasha 1950: emission occurs from lowest excited state of given multiplicity (S1 fluorescence, T1 phosphorescence) regardless of excitation wavelength; explains independence of fluorescence spectrum from lambda_ex.