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 Organic
Electronics: A Molecular View of Charge Transport in π-Conjugated
Materials
Conjugated organic oligomer and polymer materials are being
increasingly
considered for incorporation as the active semiconductor elements
in devices such
as light-emitting diodes, photo-voltaic cells, or field-effects
transistors. In the
operation of these devices, electron-transfer and energy-transfer
processes play a
key role, for instance in the form of charge transport, energy
transport, charge
separation, or charge recombination.
We have used the Atomistix ToolKit (ATK)[3,4] to model the
spin-dependent transport across MgO
layers coupled with Fe electrodes, and investigated how the
interface structure and defects in the MgO
layers affect the spin transport. The results of the calculations
will be discussed, and compared with
experimental studies. Here, we provide a theoretical description
of electron-transfer phenomena based on electron-transfer
theory, which allows us to provide a molecular, chemically-oriented
understanding.
In this presentation, we focus on the parameters that impact
the mobility of charge carriers, that is the
electronic coupling within chains and between adjacent chains
and the reorganization energy of the
chains upon ionization. Materials under study include conjugated
oligomers such as oligoacenes,
oligothiophene-acenes, oligothiophenes, and oligothienacenes.
Jean-Luc Brédas received his Ph.D. in Chemistry
from the University of Namur, Belgium, in 1979 under the supervision
of Jean-Marie André. After a joint postdoctoral stay
at MIT with Bob Silbey and the (then) Allied Chemical Corporate
Research Center in Morristown, New Jersey, with Ron Chance
and Ray Baughman, he went back to Namur in 1981 as a Research
Fellow of the Belgian National Science Foundation. In 1988,
he was appointed Professor at the University of Mons-Hainaut,
Belgium, and Head of the Laboratory for Chemistry of Novel
Materials.
While keeping an “Extraordinary Professorship” appointment
in Mons, Jean-Luc Brédas joined the University of Arizona
In 1999 before moving in 2003 to the Georgia Institute of
Technology. At Georgia Tech, he is currently Professor of
Chemistry and Biochemistry and the Georgia Research Alliance
Eminent Scholar and Chair in Molecular Design. He also serves
as Co-Director of the Center for Computational Molecular Science
and Technology. He is the recipient of the 1997 Francqui Prize,
the 2000 Quinquennial Prize of the Belgian National Science
Foundation, the 2001 Italgas Prize for Research and Technological
Innovation (shared with Richard Friend), and a member of the
team that was awarded the 2003 Descartes Prize of the European
Union. He is ranked #76 on the list of the 100 most cited
chemists for the period January 1995-June 2005. Since 2001,
he is a member of the European Research Advisory Board –
EURAB – for Science, Technology, and Innovation (EURAB
is considered as the EU equivalent of the National Science
Board).
The research interests of his groups focus on the computational
design of novel organic materials with remarkable electrical
and optical properties.
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