Self-organization of inorganic nanocrystals opens a new and challenging area in nanotechnology [1, 2]. We already know that nanomaterials are a new generation of advanced materials that are expected to exhibit unusual chemical and physical properties, different from those of either the bulk materials or isolated nanocrystals [3–5]. Engineering of nanophase materials and devices is of great interest in several domains such as electronics, semiconductors, optics, catalysis, and magnetism. During the past decade, nanocrystal research has been focused on two major properties of finite-size materials: quantum size effects and surface/interface effects [6, 7]. A new trend, however, has emerged in the past few years: the arrangement of the nanocrystals into two- and three-dimensional (2D and 3D) superlattices.