Significance of the excitonic intensity borrowing in the J-/H-aggregates of bacteriochlorophylls/chlorophylls.
A quantitative analysis of the excitonic intensity borrowing for the J-/H-aggregates of the bacteriochlorophylls/chlorophylls (BChls/Chls) in specific, and of porphyrins in general, is presented. The analysis is based on the argument that the mixing between the two energetically well-separated bands, such as the Q and B bands of BChls/Chls, should be considered important if the aggregated system possesses an excitonic superstate. A remarkably simple explanation of the significance of the excitonic intensity borrowing is given: superhyperchromism is manifested by the mediation of interband coupling between the superstates in the two well-separated bands of such aggregates. A comprehensive discussion on the significance of superhyperchromism and on its size-dependence is provided in connection with its effects on the absorption spectra of the BChl/Chl J- and H-aggregates.
Gülen
Demet
D
Physics Department, Middle East Technical University, Ankara, Turkey. dgul@metu.edu.tr
D001429:Bacteriochlorophylls / Q000378:metabolism*; D004735:Energy Transfer; D010788:Photosynthesis / Q000502:physiology; D011166:Porphyrins / Q000378:metabolism
D001429:Bacteriochlorophylls; D011166:Porphyrins