Electronic Structure and Spectroscopy of Cadmium Sulfide Clusters

摘要

There has been extensive study, both experimentally and theoretically, on how asemiconductor nanocrystal evolves to a bulk material and how its corresponding electronic properties change. Experimental observations show a close relationship between the size of nanocrystals, the lowest energy optical absorption peak and the highest energy band of the luminescence spectrum. These are usually assigned to the transition between the valence band and the conduction band or, in the molecular analogy, between HOMO and LUMO. Among the significant issues are the size-dependent shift of the lowest energy transition and its oscillator strength, the geometry of nanocrystals and its effect on the electronic structure, and the location of electron-hole pairs in real space. jg p3.