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Dear Colleagues,<br><br>
The G.R. Harrison Spectroscopy Laboratory and the Department of
Electrical Engineering and Computer Science would like to invite you to
the next seminar in our series on Modern Optics and
Spectroscopy.<br><br>
Date & Time:<x-tab> </x-tab>Tuesday, April 13,
12 noon 1 PM<br><br>
Location:<x-tab> </x-tab>Grier
Room (34-401)<br><br>
Speaker:<x-tab> </x-tab><x-tab> </x-tab><b>Paul
Barbara</b>, University of Texas at Austin<br><br>
Title:<x-tab> </x-tab><i><x-tab> </x-tab>F-V/SMS:
A New Technique for Studying the Structure and Dynamics of Single
Molecules and Nanoparticles<br><br>
<br>
</i>Refreshments will be served following the talk.<br><br>
<br>
Abstract:<br><br>
<b>Paul Barbara</b>, University of Texas<br>
<i>F-V/SMS: A New Technique for Studying the Structure and Dynamics of
Single Molecules and Nanoparticles<br>
</i>We recently introduced a new technique for semiconductor nanoparticle
research that involves simultaneous single molecule spectroscopy (SMS)
<i>and</i> controllable oxidation/reduction in an electronic
device. The new technique (denoted by fluorescence voltage F-V/SMS)
is analogous to current vs. voltage (<i>I-V</i>) measurements for devices
and electrochemical cells. F-V/SMS data are reported for single molecules
(nanoparticles) of the conjugated polymer MEH-PPV as a function of bias
voltage on the device and bias sweep rate to obtain information on both
the energetics and kinetics of the charge transfer (oxidation/reduction)
process in situ on the nanoscale. The extensive F-V/SMS data
presented in the talk reveal that the dynamics for oxidation/reduction of
MEH-PPV nanoparticles are controlled by various factors including filling
of deep hole traps in the charge transporting layer of the device, the
oxidation/reduction chemical “state” of the MEH-PPV molecule, and the
molecular scale heterogeneity of the device.<br><br>
<br><br>
<x-sigsep><p></x-sigsep>
Vinnie Russo * vrusso@mit.edu * Office Manager<br>
MIT; G.R. Harrison Spectroscopy Laboratory<br>
77 Mass. Ave., 6-014 * Cambridge, MA 02139<br>
(v) 617-253-9774 * (f) 617-253-4513</html>