29 Oct 2009 Nanostructural materials of unique physical and electronic properties are the building blocks of electronic and optical devices and other functional materials, which have great potential for developing new nanotechnology including applications as drug carriers, biolables, photovoltics, light emitting diodes and lasers. New synthetic methods have been developed to achieve complete control over the shape of the nanocrystals and to prepare more complex-shaped nanostructures such as a few dots linked together forming nanochains, rods linked together to form tetrapods, coating the nanocrystals with another layer a different material, or even doping the nanocrystal with another different atom. Such control over linking, branching, coating or doping throughout the growth of the nanocrystals allows more potential applications ranging from information processing to artificial photosynthesis. In addition, the possibility of using these nanostructural materials to be used in high performance solar cells and optoelectronic devices will be exposed. Factors affecting the shape of the nanocrystals will be discussed. The new optical properties associated with these new shapes will be revealed. Mona Bakr Mohamed