AVS 53rd International Symposium
    Nanometer-scale Science and Technology Tuesday Sessions
       Session NS1-TuM

Paper NS1-TuM12
Electronic Structure Studies of CdSe Nanocrystals Using Synchrotron Radiation

Tuesday, November 14, 2006, 11:40 am, Room 2016

Session: Nanoscale Structures and Characterization II
Presenter: R.W. Meulenberg, Lawrence Livermore National Laboratory
Authors: R.W. Meulenberg, Lawrence Livermore National Laboratory
J.R.I. Lee, Lawrence Livermore National Laboratory
L.J. Terminello, Lawrence Livermore National Laboratory
T. van Buuren, Lawrence Livermore National Laboratory
Correspondent: Click to Email
We have examined band edge shifts in colloidal CdSe nanocrystals using synchrotron radiation. In particular, Cd s states located at the conduction band minimum (CBM) show drastic size dependencies while the Cd d levels located a few electron volts up from the CBM show more localized behavior. This was not expected based on effective mass theories, although more sophisticated calculations are shown to agree better with experiment. Changing the surface ligand has very little effect on the shift of the band edges, but does affect the local bonding significantly. In addition, we find that the electronic structure can further be tuned by the incorporation of dopant atoms. Our experimental findings will be compared with recent theory to help resolve the nature of quantum confinement in CdSe nanocrystals. This work was supported by the Division of Materials Sciences, Office of Basic Energy Science, and performed under the auspices of the U.S. DOE by LLNL under contract No. W-7405-ENG-48.