OPTICAL-PROPERTIES OF NANOSIZED PARTICLES DISPERSED IN COLLOIDAL SOLUTIONS OR ARRANGED IN 2D OR 3D SUPERLATTICES

In this paper it is demonstrated that colloidal assemblies used as tem plates are good candidates for controlling the size and shape of nanop articles. The optical properties of metal nanoparticles dispersed in a colloidal solution differ with size and shape. When these particles a re able to self-assemble, they form monolayers in a hexagonal network or crystal with a face-centered cubic arrangement. Such self-organizat ions induce changes in the optical properties. The size and compositio n of II-VI semiconductors are controlled independently. Quantum dots a re observed. For semiconductor semimagnetic nanocrystals such as Cd1-y MnyS, the fluorescence due to isolated Mn2+ ions is attributed to the aging of the particles and not to a quantum dot effect, as predicted.