Optical absorption spectra of LH I and LH II of purple bacterial photosynthetic systems: an electrodynamical approach based on recent structural determinations

Electronic absorption spectrum in the near IR region (Q(y) band) of LH I of Rhodopsirillum rubrum and LH 11 of Rhodopseudomonas acidophila is calculat ed using an electrodynamical point dipole approximation. The model uses the geometrical arrangement and the properties of individual chromophores made available from recent structural and spectroscopic determinations and is f ound to accurately predict not only the resonance frequencies, but also the shape of the Q(y), band of the absorption spectrum.