CHARACTERIZATION OF CDSE NANOCRYSTALLITE DISPERSIONS BY SMALL-ANGLE X-RAY-SCATTERING

We use x-ray scattering at small angles (SAXS) to study interparticle interactions in dilute dispersions of CdSe nanocrystallite particles. In particular, we probe the dependence of these interactions on a few key parameters, including the nature of the cap molecules attached to the surface of the particles and the solvent. Alkyl capped nanocrystal lites with relatively long hydrocarbon chains are stable in a range of solvents. Nanocrystallites capped with smaller molecules show attract ive interparticle interactions. Existence of association (e.g., dimers and trimers) in dispersions characterized by attractive interactions is observed in the scattering data for pyridine capped particles. (C) 1996 American Institute of Physics.