020 



480 



640 



520 560 600 



WAVE LENGTH, m/i 



Fig, 21.9. Absorption spectrum of porphin (;ifter Stern, 

 Wenderlein and Molvig 193G). 



green X red green \ red green X red 



Fig. 21.10. Typical spectra of porphin derivatives above 500 m^i (not showing the 

 strongest band, at 420 niju) (after Stern 1938). (1, 2, 3) porphyrin spectra; (4. 5) 

 chlorin spectra; (6) bacteriochloriu spectrum. 



