Research Interests
My research interests are in ultraviolet-visible
spectroscopy of organic compounds which undergo charge transfer.
Such compounds have important applications as biological probes and potential
applications for information storage and harvesting of light energy.
When many such molecules absorb light, they form an excited state which
is much more polar than the ground state. This highly polar state
is sensitive to the polarity of the solvent. Because of this there
may be large changes in the absorption and fluorescence spectra as the
solvent is changed from nonpolar to polar. In addition to changes
in the spectra, the molecules themselves may change conformation, or
shape.
The molecule shown below is dimethylaminobenzonitrile, DMABN, and is believed
to be nearly planar in the ground state as shown on the left. In
the excited state, there may be a twist of the dimethylamino group so that
it is perpendicular to the benzene ring, as shown on the right.
I am currently studying compounds that are similar to DMABN by absorption
and fluorescence spectroscopy. In addition, I perform numerical molecular
orbital calculations on the compounds by several techniques, using programs
for the PC and on the Cray supercomputer of the
Alabama
Research and Education Network (AREN).
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