Magnetic Resonance: Metal Hydrides and Innovative Techniques

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w:\awards\awards96\num.doc 9705080 Conradi This experimental research project is based on NMR techniques, and has two main thrusts: (1) study of metal hydrides and (2) development of innovation in NMR technique. The work on hydrides (1) focuses in one case on motion of hydrogen or deuterium in elemental hcp dilute hydrides, in the temperature range near 60- 80K. In a second aspect, the YH2-YH3 system, with possible application as a switchable mirror, will be examined. (2) Spin- echo double resonance (SEDOR) will be extended as an NMR technique in such a way that the echo amplitude A will be measured as a function of the flip angle on the unobserved spins.This new method will be applied to amorphous hydrogenated silicon. The nuclear Overhauser effect (NOE) will be exploited to enhance the use of optical techniques, which have previously been developed by others to provide 20-50% nuclear spin polarization of helium 3 or Xe 129. The nuclear Overhauser effect will be used to transfer some of this polarization to spins of analytical importance, such as protons and C13. An additional application of the NOE will be made in a proposed technique to avoid inhomogeneous broadening in NMR study of dilute solute resonances in a solvent. %%% This experimental research project is based on the technique of nuclear magnetic resonance. In one aspect of the work, the hydrogen or deuterium resonance in metal hydrides will be studied to clarify the state of motion of hydrogen or deuterium ions in the hydride structure. Metal hydrides are of interest for potential use as an energy storage medium. In a second aspect of the work, the project will research an enhancement of the nuclear magnetic resonance technique, in conjunction with a separately developed nuclear spin polarization technique. The new method will make use of the nuclear Overha user effect, and may permit new applications of nuclear magnetic resonance in analytical studies. Secondly, in solutions, where a dilute solute is of interest, the new method will greatly reduce the broadening which arises from interaction with the solvent molecules. This research project is interdisciplinary in nature and involves graduate and postgraduate students who will be excellently trained to enter positions in industry, government or education. ***