Abstract: There is a considerable interest in producing and understanding the optical and spectroscopic properties of ordered nanoparticle assemblies. Herein, we describe and interpret the optical absorbance and Raman properties of 5.9 nm ± 0.3 nm diameter silver nanocrystals coated with dodecanethiol and organized in highly ordered 3D superlattices of different heights. Each superlattice was studied individually, which allowed to elaborate a model based on Maxwell-Garnett theory to reproduce qualitatively the height and wavelength dependence of the absorbance...