title: Bimodal bond-length distributions in cobalt-doped CdSe, ZnSe, and Cd1-xZnxSe quantum dots.
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.
authors.affiliation: Department of Chemistry, University of Washington, Seattle, WA 98195-1700, USA.
authors.forename: Steven A
authors.initials: SA
authors.lastname: Santangelo
authors.forename: Eric A
authors.initials: EA
authors.lastname: Hinds
authors.forename: Vladimir A
authors.initials: VA
authors.lastname: Vlaskin
authors.forename: Paul I
authors.initials: PI
authors.lastname: Archer
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Gamelin