STABILITY OF CDS NANOCRYSTALS IN GLASS

We have measured and analyzed optical absorption and x-ray absorption spectra of CdS nanocrystals Brown by solid-state reaction in a borosil icate glass, with average crystallite radii from 1.4 to 5 nm. The firs t (Cd-S) and second (Cd-Cd) neighbor distances are within 0.2% of the bulk values in all cases. We establish an upper bound for the interfac ial tension of 0.15 N/m. Such low interface tension suggests that glas s-embedded nanocrystals are inherently more stable than bare or capped nanocrystals of the same size.