Single Molecule Spectroscopy
We have a number of projects examining heterogeneous systems on a single molecules basis. By spatially isolating high fluorescent probes it is possible to detect the fluorescence from individual molecules. These molecules can then act as reporters of their local environment. The intensity, emission spectrum, lifetime, and polarization of the molecules can be followed in time to see how these environments evolve.
Probing polymer environments
We are interested in using single molecules to probe polymer thin films in
two projects. In the first we are seeking to understand the origins of
non-exponential relaxations in polymer thin films near their glass transition.
Here we are using the rotational diffusion of individual dye molecules to probe
the polymer dynamics. In a second project, we are using polarity sensitive dyes
to probe local environment in proton exchange membranes for use in fuel cells.
(Student: Katie Clark)
Single Conjugated Molecules
We are also studying single conjugated molecules to help understand the role of
morphology in their emission spectra. By isolating individual chains we can probe
the role of chain conformation on the emission spectra as well as study systems
with limited energy transfer.
(Student: Yeon Ho Kim)
|
| Spectrum of individual poly(dioctylfluorene) molecules isolated in polystyrene |