Upgrade of a 400 MHz NMR spectrometer for Research on Solid and Molten Materials in the Earth and Materials Sciences

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EAR-0235360StebbinsNuclear Magnetic Resonance (NMR) spectroscopy is an analytical tool that provides unique information on atomic-scale structure and dynamics for solid and molten materials of wide importance in the earth and materials sciences. This award funds an upgrade of an instrument that has been used for 15 years to carry out a wide range of pioneering studies in this field, that had aged to the point of being almost non-repairable. The research to be continued with this instrument (also funded by NSF) emphasizes the intriguing and complex problems of disordered crystalline and glassy solids, and their glass-forming liquid precursors. NMR studies of such materials have contributed greatly to the fundamental understanding of the macroscopic properties that are needed to model and predict their behavior in large-scale processes in nature and in technology. For example, the P.I.'s group is quantifying the proportions of different types of oxygen linkages between network cations in geological aluminosilicate glasses and in technological borosilicate glasses, and is using these data to calculate effects of this disorder on the energetics of the melts, to predict changes with temperature, and to relate the resulting thermodynamic properties to free energy, phase equilibria, and viscous flow. Other ongoing projects include studying the role of elements such as fluorine and hydrogen in high-tech optical glasses, the structure of zeolite minerals important in areas as diverse as metamorphic rocks, radioactive waste sequestration, and catalysis in the oil industry, and new work on natural biological materials and organic environmental contaminants.***