Nuclear Magnetic Resonance Methods for Non-Crystalline Solids

Ohio State University, The, Columbus OH

Investigators

Abstract

In this project, funded by the Chemical Measurement and Imaging Program of the Chemistry Division, Professor Philip Grandinetti of the Ohio State University will develop new nuclear magnetic resonance (NMR) methods for elucidating structure in non-crystalline materials. There are many unresolved questions in these materials regarding atomic structure at different levels, from short range, i.e., first coordination sphere structural distributions, to intermediate range, e.g., chain and ring size statistics. It is possible for NMR to provide information at all these levels, either alone, or complemented by other measurements or modeling. To do this, however, much work is needed to build up an infrastructure of methods and a full understanding of the relationships between NMR parameters and structure. Structural distributions obtained in this project will be valuable in confirming thermodynamic models of glasses and melts, models for ionic transport, and also in refining potentials in molecular dynamics simulations of structure and dynamics in glasses. Such details can have far reaching impact. For example, radioactive waste is commonly mixed into glass melts for long term containment, and environmental policy decisions will require accurate scientific data on the long term effectiveness of glass as a storage material, which in turn, will require a deeper understanding of transport properties that depends strongly on the atomic level structure. These new methodologies will also impact other fields such as ceramics, catalysts, biopolymers, which can utilize the same resources and methodology developed for our applications. The long term goal of this project is to create standard NMR protocols and software for materials scientists enabling them to obtain enough atomic and molecular level structure statistics to design and synthesize new materials. Beyond materials science applications, methods developed in this project for selective NMR excitation of quadrupolar nuclei in solids can even be used for contrast in magnetic resonance imaging, and could eventually lead to improved medical diagnosis and treatment. As such, one can expect a number of these magnetic resonance methodologies to be incorporated into commercial products. Students trained in this project include members of various under-represented groups.