Recent Progress on Modeling H Passivated CdS Nanocrystals using ab initio techniques*

Spherical CdS nanocrystals with shells of H atoms are studied via an \textit{ab initio} tight-binding analysis. Starting from the bulk zinc blende structure of CdS, these nanocrystals undergo relaxation as the geometries optimize to configurations that minimize internal forces. H atoms are then attached, to passivate the surface, and then whole structure is relaxed. We will present our latest results.