Effects of Particle Size and Capping Entities on Nanocluster Properties

Capped cadmium and zinc sulfide compounds of varying particle size have been synthesized. The particle size is determined using the Brus equation and can be varied by modification of the concentration ratios of cadmium sulfate, sodium sulfide and the capping group, all of which are prepared using aqueous solutions.~ Nuclear magnetic resonance and thermal gravimetric analysis are used to determine the amount of coverage of the nanoparticle surface by the capping molecule. Additional information about the tumbling rates of cadmium and zinc sulfide nanoparticles and the associated motion of the capping groups can be determined from linewidth studies.~ Accurate fitting of the global tumbling parameters indicate that particle size and capping entity play a significant role.