“…The self-assembly of colloids into larger periodic structures is a phenomenon commonly observed in nature. For example, opals form by colloidal crystallization of highly monodisperse spherical particles with diameters in the 100–1000 nm range. − In the last two decades, there has been more and more focus on colloids with sizes in the nanometer range . Assembly of colloidal nanocrystals (NCs) dispersed in nonpolar solutions has been studied extensively. − Single- and binary-component NC superlattices have been realized as three-dimensional crystals, , thin films, and in some cases even as two-dimensional sheets with a large variety of NCs. ,,− In this field of nanoscience, there is a quest to design superstructures with tunable optical, magnetic, and electric properties that emerge from the properties of the building blocks, and the quantum mechanical and dipolar interactions between them. , …”