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There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
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Prof. Jonathan Owen, Columbia University
The coordination chemistry of cadmium selenide nanocrystals
School Colloquium
Surfaces dominate the properties of colloidal semiconductor nanocrystals. Characterizing and controlling surface coordination chemistry is therefore crucial to their application in optoelectronics and fluorescence labeling. I will describe our picture of nanocrystal surface structure as well as a novel ligand exchange technique that allows us to fabricate semiconductor films using solution techniques. In particular, we have exchanged carboxylate ligands for chloride ligands in the presence of alkylphosphines and prepared thin film transistors with unusually high electron mobilities (8 cm^2/V/sec). In addition, using 31P NMR spectroscopy we monitor the binding and exchange of tri-n-alkylphosphines and can estimate the relative binding affinities of amines, phosphines and phosphine oxides. I will also briefly discuss our work on the structural characterization of large semiconductor molecules or molecular clusters.
For more information contact Prof. Joseph Sadighi (404-385-2244).
