Deuterium NMR has the capacity to provide dynamic information on the 101-1010 sec-1 time scale, making it ideal for probing molecular mechanics. Deuterium quadrapole echo spectroscopy was used to study the dynamics of the CD3 groups in a labelled single crystal of N-Acetyl-DL-Valine and the dynamics of the water coordinated to barium chlorate in its polycrystalline form. Temperature dependence, spectral intensities, and anisotropy of the 2H spin-lattice relaxation were used to determine the rates and mechanisms of motion of the coordinated water. Empirically obtained spectra were compared with computer simulations of deuterium lineshapes and found to be consistent with a twofold jump model. A study of the methyl-group dynamics of N-acetyl-DL-valine was carried out to demonstrate the feasibility and accuracy of this technique. A single crystal was used to determine the activation energies for both methyl groups based on a threefold jump model. The two groups have different activation energies and using single crystal measurements, it was possible to assign the activation energies to the correct motions. The accuracy of this technique on model compounds suggests that its application to biochemical problems is feasible.
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