Significance of the excitonic intensity borrowing in the J-/H-aggregates of bacteriochlorophylls/chlorophylls

Gulen D.

PHOTOSYNTHESIS RESEARCH, cilt.87, sa.2, ss.205-214, 2006 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Cilt numarası: 87 Konu: 2
  • Basım Tarihi: 2006
  • Doi Numarası: 10.1007/s11120-005-8408-2
  • Sayfa Sayıları: ss.205-214


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.