Fig. 3. Calculated spatial distribution of the normalized electric field amplitude for (a) one triangular sublattice and (b) two superposed triangular sublattices for the SLR. The calculations are for s-polarized light and normal incidence. The dashed circles in (a) represent the position of the missing non-equivalent sublattice. (c) s-polarized extinction spectra calculated at normal incidence for the two non-interacting triangular lattices (orange curve) and for the honeycomb lattice (blue curve).