November 1, 2006
Interschool Lab, 7th floor, Schapiro/CEPSR
Hosted by: Mark Hybertsen - CISE
Speaker: Harold U. Baranger, Duke University
To describe conduction through a single molecule requires combining accurate chemical information with a suitable transport model. A standard approach is to find the transmission of single-particle states described by density functional theory using a local exchange correlation (xc) functional. We have used this approach to study the possibility of organometallic spintronics in molecules containing two cobaltocene moieties. To test and extend the standard methodology, we construct new xc potentials based on the optimized effective potential (OEP) approach and calculate electron transmission through two atomic chain systems, one with charge transfer and one without. For systems that may have charge transfer, the presence or absence of self-interaction error plays a key role. We find that the OEP approach changes the LUMO state and the HOMO-LUMO gap, thereby dramatically altering the calculated molecular conductance.