Figure 4.

GMMT simulations of the longitudinal modes calculated with a constant interparticle distance of 1.5 nm and varying chain lengths: extinction spectra of single particle (A) and dimer (B) lines are shown for chain lengths up to 60 repeat units. The normalized extinction is mapped for all chain lengths in the image plots below the graphs. For both chain types, the energy of the superradiant mode converges toward a fixed value around 10 repeat units. Additional subradiant modes that occur with increasing chain length converge to the spectral position of the superradiant mode.