Ultrafast
Spectroscopy of Transition Metal Complexes
Research efforts in this area are concerned with
the short timescale photo-induced dynamics of transition metal complexes.
By
“short timescale”, we refer to processes occurring between the time a
photon is absorbed by a molecule and the point at which that molecule
is fully relaxed in its lowest-lying excited state. Some of
the
questions we are addressing with this research include the following:
1) what is the general timescale for excited-state evolution in
transition metal complexes? 2) what is the mechanism of this process?
3) how do the geometric and electronic structures of the compounds, the
surrounding medium, and other factors couple to and/or influence this
process? and 4) to what extent can we use this information to control
excited-state dynamics? Some of these questions are very
fundamental in nature, whereas others are geared toward applications involving solar
energy conversion or catalysis. What distinguishes this group, we believe,
is
our ability to carry out both the synthesis and spectroscopic
characterization of a wide range of inorganic molecules. This
enables us to systematically examine chemical perturbations to
excited-state electronic and geometric structure, and as a result,
develop a comprehensive picture of how transition metal chromophores
absorb and dissipate energy.
Solar/Ultrafast
Sub-Group Research Summary (pdf)
Electron
Exchange and Chemical Dynamics
Electron exchange is a term which describes the
electrostatic interactions that can exist among unpaired electrons in
molecules. Our group is interested in understanding the influence
electron exchange has on the chemistry of inorganic
compounds.
Metal-quinone complexes provide the framework for studying the
photophysics of exchange-coupled molecules. The redox
activity of
the quinone ligand provides a facile mechanism for turning “on” or
“off” electron exchange, allowing us to probe the effects of spin
coupling on excited-state dynamics in closely related sets of chemical
systems. A second area concerns reaction dynamics, where the
emphasis is on electron and energy transfer processes in polynuclear
metal clusters. Through detailed studies of synthetically
tailored molecules, we are examining whether or not the electron
exchange interactions present in such clusters plays a functional role
in their reactivity.
Coupled to this experimental work are theoretical
studies that exploit recent advances in density functional
theory. We believe that these combined efforts will allow us
to
forge an important link between magnetism and the electron/energy
transfer chemistry of molecules, as well as provide insights into the
possible role of electron exchange in the biochemistry of
metalloproteins.
Spin Sub-Group Research
Summary (pdf) Synthesis Poster Fall 2016 (pdf)
|