Magnetic resonance studies of molecular structure and dynamics

核磁共振（NMR）波谱学和磁共振成像（MRI）将用于提供对化学，材料科学和工程中的重要问题的见解。我们特别感兴趣的是更好地理解在核磁共振实验中测量的基本参数与分子结构之间的关系。我们将利用固体材料的核磁共振研究提供的一个机会来表征描述这些参数的张量，而不是它们的各向同性值。相当大的努力将用于核磁共振成像中使用的对比剂等顺磁性固体的核磁共振研究。从这些研究中获得的信息以及探索这些材料的现代技术的局限性还没有得到很好的理解。我们将使用国家固体超高场核磁共振设备来探索高场核磁共振波谱的潜力，特别是在研究尚未得到很好研究的重要非整数自旋四极核（例如，As-75, Sb-121）方面。我们最近成功的应用核磁共振显微镜来研究运行中的聚合物电解质燃料电池中的水分布将得到扩展。近期目标包括：提高1H NMR图像的空间分辨率，改进水的量化，检测石墨毡气体扩散层中的水，并将我们的方法扩展到酒精燃料电池。了解燃料电池运行中的水分布对于开发更可靠的聚合物电解质燃料电池模型至关重要。我们将继续使用热极化和超极化Xe-129核磁共振研究对多孔材料进行核磁共振研究。在与分子筛纳米材料研究中心的Steve Kuznicki合作中，我们使用了氙-129核磁共振以及Al-27、Si-29和Ag-109核磁共振来研究一些潜在的重要的银交换分子筛，这些分子筛的应用包括氩氧气体分离。最后，我们将独立工作，并与新西兰惠灵顿维多利亚大学的Paul Callaghan合作，开发核磁共振在地球磁场中的应用。

Nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI) will be used to provide insights into important problems in chemistry, materials science and engineering. We are particularly interested in gaining a better understanding of the relationship between the fundamental parameters that one measures in an NMR experiment and molecular structure. We will take advantage of the fact that NMR studies of solid materials provide one with an opportunity to characterize the tensors that describe these parameters instead of their isotropic values. Considerable effort will be devoted to NMR investigations of paramagnetic solids such as contrast agents used in MRI. The information available from such studies as well as the limitations of modern techniques in probing these materials is not well understood. We will use the National Ultrahigh-Field NMR Facility for Solids to explore the potential of high-field NMR spectroscopy, particularly in studying important non-integer spin quadrupolar nuclei that have not been well studied (e.g., As-75, Sb-121). Our recent successful applications of NMR microscopy to study water distribution in operating polymer electrolyte fuel cells will be extended. Immediate goals include: improving the spatial resolution of our 1H NMR images, improving water quantification, detecting water in the graphite-felt gas diffusion layer and extending our methodology to alcohol fuel cells. Knowledge of water distribution in operating fuel cells is absolutely critical in developing more reliable polymer electrolyte fuel cell models. Our NMR investigations of porous materials using thermally polarized and hyperpolarized Xe-129 NMR studies will continue. In collaboration with Steve Kuznicki, a CRC in Molecular Sieve Nanomaterials, we are using Xe-129 NMR as well as Al-27, Si-29 and Ag-109 NMR to examine a number of potentially important silver-exchanged molecular sieves that have applications that include argon-oxygen gas separation. Finally, we will be working independently and in collaboration with Paul Callaghan at Victoria University in Wellington, New Zealand to develop applications of NMR in the Earth's magnetic field.