Xenon as a Probe of Internal Space in Fluids and Porous Media

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Professor Cynthia Jameson of the University of Illinois at Chicago is supported in the Experimental Physical Chemistry program to perform Nuclear Magnetic Resonance (NMR) studies utilizing Xenon atoms to probe environments difficult to study such as the interior of zeolites, polymers and biomolecules. Her goal is to use these experiments together with ab initio predictions of chemical shift parameters and more standard Monte Carlo statistical models to develop Xenon NMR as an exact quantitative method. Xenon NMR is widely used to study solid samples, but it has not yet been exploited to its full potential. For example, her group will develop the method for accurate determination of competitive adsorption of molecules in zeolite cavities, a key parameter in understanding the catalytic power of zeolites. The effect of counterions in cation-exchanged zeolites will be studied, as well as some kinetics and dynamical studies on these systems. The experiments will provide testing grounds for new theory - improving the potential surfaces between Xenon and coadsorbates (or the zeolite wall) as well as the statistical models for adsorption in zeolites. The experience with zeolites will then be applied to the problem of structure of liquids, polymers, and biological systems. Professor Jameson will conduct mainly theoretical studies analyzing Xenon NMR signals in cyclodextrin, polymers, polymer blends and in globular proteins such as myoglobin, with the goal of understanding the structures of these microheterogeneous chemical environments.Nuclear magnetic resonance (NMR) is a chemical version of the more well-known medical method Magnetic Resonance Imaging (MRI). The use of NMR for understanding basic structural features of solids, liquids, and gases is increasing with the development of new techniques such as Xenon NMR, which has been used to study solid-state structures. The research is timely also due to the recent use of hyperpolarized Xenon for imaging (including clinical applications). In addition to interesting the catalysis community studying zeolites, the work will ultimately be of use in other applications of microporous solids such as separations. Professor Jameson is well known as an outstanding mentor of women and minorities in her laboratories.