Figure shows FDTD simulated extinction ≡ 1 -, as well as absorption, scattering and extinction cross-section (respectively abs , sca , ext ) spectra of MIM metasurfaces with fixed = 400 nm disc diameter and = 800 nm period values, but varying SiO 2 spacer thicknesses. At this period-to-diameter ratio of / = 2 the interaction between adjacent nanodiscs (plasmonic gap mode) is negligible. Even if a collective grating effect is present, the optical properties of the metasurface are primarily defined by the interaction between dipole resonance of the individual nanodiscs and their induced mirror-charge oscillations in the metal ground plate . Therefore, when the spacing between nanodisc and ground plate become smaller, the dipole-induced interaction is enhanced, causing a red-shift in the resonance wavelength. Both absorption and scattering are defined by the resonant interaction between a nanodisc and ground plate; sca increases for a thicker SiO 2 layer. This series of simulations revealed that both abs and sca are prominent at the minimum specular reflectance condition when overall extinction = 1is at its maximum.