Resonant raman effect of hematoporphyrin IX in the α, β absorption band of the Q(π→π*) electronic transition

Resonant Raman spectra of hematoporphyrin IX have been obtained in methanol, acetone and acetic acid. Excitation RR profiles show that intensity enhancements, due to the vibronic excitation process, are active for some normal vibrations of the macrocycle and for motions of the lateral groups. Line-width-lifetime correlations and molecular-association processes are discussed.