Assistant Professor of Chemistry
University of Wisconsin, Ph.D.
Prof. David Thompson joined the department in the fall of 2002. He studied as an undergraduate at Carleton College; taught middle school science with the Peace Corps in Ghana, West Africa; received a Ph.D. in chemistry under the mentorship of Dr. John Wright at the University of Wisconsin, Madison and spent several years engaged in post-doctoral physical chemistry research under the mentorship of Dr. Michael Fayer at Stanford University. Dave's core courses at Lawrence include Analytical Chemistry (CHEM 210) and Instrumental Analysis (CHEM 410), along with contributions to the teaching of introductory chemistry (especially CHEM 116) and the chemistry seminar series (CHEM 380, 480 & 680.)
Dave has extensive experience with nonlinear optical laser spectroscopy experiments,
most recently in ultrafast infrared vibrational spectroscopy. This is an area
of cutting edge research that holds much promise; but which is currently challenging,
in part because many nonlinear optical signals are very weak. Currently, Prof.
Thompson and the Lawrence students who work with him are developing a research
program that investigates the environmental properties that influence the strength
of the signals observed in various types of laser experiments. The novel aspect
of this work lies in bringing together mesoporous materials and resonance enhanced
Raman spectroscopy research. Researchers around the world have found that in
the presence of nanoscale roughness it is possible to greatly strengthen the
signals arising from laser induced Raman spectroscopy. Prof. Thompson believes
that one way to create very regular arrays of such nanoscale roughness is to
grow gold particles in the tiny “honeycombs” of mesoporous materials.
Toward this end his research group has been outfitting a lab to synthesize
mesoporous silica materials with regulary arrayed pores with a smallest internal
dimension falling in the range of 2-50 nm. Over the past summer the group was
able to successfully replicate some of the mesoporous syntheses reported by
other groups working in this area. In the coming months the group has numerous
ambitious goals.
(1) They will be pressing forward to improve syntheses and methods of pore
characterization using tools such as transmission electron microscopy and scanning
tunneling microscopes.
(2) They will be ordering optical equipment and lasers to set up the spectroscopy
side of the experiment.
(3) The group will be developing methods of reproducibly filling these porous
materials with gold and etching away a small layer of silica near the surface
to leave an exposed pattern of tiny gold rods protruding from its surface.
In successive syntheses the group then plans on systematically altering variables
such as pore size, gold rod aspect ratio, and the spacing between rods. After
each synthesis, molecules will be laid down on the surface and probed using
laser induced Raman spectroscopy. This will enable us to develop a deeper understanding
of how we might tailor challenging laser experiments so as to strengthen the
extraordinarly weak signals of many chemical phenomena so that they can be
more accurately observed and studied.
Dr. Thompson also has a deep interest in the chemistry of malaria, and in the future hopes to bring some of the laser spectroscopic methods described in the above paragraph to the study of drug, cell membrane interactions that are important in the chemotherapy of this disease.
email: David.Thompson@lawrence.edu