Covalency in semiconductor quantum dots

Chemical schemes for the preparation of direct band-gap semiconductor quantum dots have advanced rapidly over the past few years. It is now possible to prepare a variety of III–V semiconductors with a finite size (InP, InAs, GaAs, etc.) and compare their size-dependent properties with the well studied II–VI class of quantum dots (ZnS, CdS, CdSe, etc.). In this Reviews, various physical properties of semiconductor quantum dots are presented within a discussion framework of lattice covalency. Included in the Reviews are discussions of the various chemical synthetic routes for making the particles, as well the electronic structure and the electronic dynamics of nanocrystals.