Grant for Exploratory Research: NMR of Reactive Intermedi- ates and Surfaces Using Spin Polarized Xe

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Professor Zilm is supported by a grant for exploratory research from the Experimental Physical Chemistry Program to develop the NMR methods which would take advantage of the newly discovered optical polarization techniques for producing nearly perfectly spin-polarized Xe-129 nuclei in xenon gas. In principle, the transfer of this polarization to nuclei in a molecule in a solid xenon matrix can be achieved for enhancement of the NMR signals by up to four orders of magnitude. These novel experiments are expected to have high impact on the detection of orders of magnitude smaller concentrations of molecules in xenon matrix isolation. This would mean that reactive species which are created in very small steady state quantities in a chemical reaction could be detected with NMR, providing detailed structural information. This would also mean that low sensitivity nuclei, such as naturally abundant carbon-13 and silicon-29 could be observed even at these low concentrations. %%% This exploratory research project will make use of the just discovered method of completely polarizing the nuclear spins in xenon by using the xenon to transfer polarization to other nuclei, thus enhancing their nuclear magnetic resonance spectra by ten thousand fold. The preliminary experiments will determine the conditions that are necessary for the efficient polarization transfer. The xenon could be used as a solid matrix for the detection of very small amounts of reactive molecules and molecule fragments. The xenon can also be laid down on a surface to allow the detection of only surface atoms.