Microscopic theory of cation exchange in CdSe nanocrystals.

  title={Microscopic theory of cation exchange in CdSe nanocrystals.},
  author={Florian D. Ott and Leo L Spiegel and David J. Norris and Steven C. Erwin},
  journal={Physical review letters},
  volume={113 15},
Although poorly understood, cation-exchange reactions are increasingly used to dope or transform colloidal semiconductor nanocrystals (quantum dots). We use density-functional theory and kinetic Monte Carlo simulations to develop a microscopic theory that explains structural, optical, and electronic changes observed experimentally in Ag-cation-exchanged CdSe nanocrystals. We find that Coulomb interactions, both between ionized impurities and with the polarized nanocrystal surface, play a key… 

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