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Much of our work focuses on the elucidation of molecular structure as a probe of weak intermole-cular interactions. Our laboratory is equipped with FTIR facilites for the collection of mid-and far-infrared Fourier transform spectra and two spectrometers for the collection of classical and resonance enhanced laser Raman spectra. This includes a spectrograph equipped with a krypton laser and a charge-coupled-device (CCD) detector that allows for rapid collection of weak signals with minimal interference from fluorescent emissions. One of our ongoing projects is the study of solvent-solute interactions in order to understand the molecular level dynamics responsible for the solvating abilities of dipolar aprotic molecules. Vibrational spectra are being analyzed using Lewis acid/base concepts and the Raman noncoincidence effect. Methods have been developed that allow the nature of molecular environments to be monitored in a straightforward manner. Recent work has focused on urea derivatives. Another area that has received considerable attention is the study of weakly bonded metal complexes. 4-(Dimethylamino)benzaldehyde and its analogues are useful chromophoric probes of enzyme and metalloenzyme catalytic pathways. Many of these molecules undergo facile bonding to transition metals and have been investigated using infrared and preresonance enhanced Raman spectroscopy. The addition of far-infrared data and normal mode analysis would add valuable information about the metal/ligand bonding in these systems. We have also investigated the 1:1 CuNO3+ complex and have analyzed its structure using mid- and low-frequency spectra, isotopic substitution and normal mode analysis. The effect of solvent molecules on the bonding characteristics of this complex remains an open question. An area of recent interest is the study of graphite and metal-catalyzed graphite oxidation. First-order Raman scattering from graphitic materials arise from nonzero center phonons in the lattice and is sensitive to surface disorder. The Raman line profiles change during the oxidation process and these changes are dependent on the presence or absence of selected metals deposited on the surface. This work is being pursued in order to understand the mechanism of the catalyzed oxidation process.
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