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Updated: Jul 16, 2026

Compact Quantum Dots for Single-molecule Imaging
Published on: October 9, 2012
Bimodal bond-length distributions in cobalt-doped CdSe, ZnSe, and Cd1-xZnxSe quantum dots
Steven A Santangelo1, Eric A Hinds, Vladimir A Vlaskin
1Department of Chemistry, University of Washington, Seattle, WA 98195-1700, USA.
Abstract:
Electronic absorption spectroscopy has been used to study changes in Co2+ ligand-field parameters as a function of alloy composition in Co2+-doped Cd(1-x)Zn(x)Se nanocrystals. A shift in the energy of the 4T1(P) excited-state with alloy composition is observed. Analysis reveals that Co2+-Se2- bond lengths change relatively little as the host is varied continuously from CdSe to ZnSe, generating a large difference between microscopic and average cation-anion bond lengths in Co2+-doped CdSe nanocrystals but not in Co2+-doped ZnSe nanocrystals. The bimodal bond-length distributions observed here are shown to cause a diameter-dependent enthalpic destabilization of doped semiconductor nanocrystals.
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