Magnetic resonance studies of molecular structure and dynamics

核磁共振（NMR）光谱和磁共振成像（MRI）将用于提供对化学，材料科学和工程中重要问题的见解。 我们特别感兴趣的是更好地了解NMR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NMR研究提供了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。 相当大的努力将致力于核磁共振研究的顺磁性固体，如造影剂中使用的MRI。 此类研究提供的信息以及现代技术在探测这些材料方面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NMR设备来探索高场NMR光谱的潜力，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）。 我们最近成功的应用核磁共振显微镜研究水分布在操作聚合物电解质燃料电池将得到扩展。 近期目标包括：提高我们的1H NMR图像的空间分辨率，提高水的定量，检测石墨毡气体扩散层中的水，并将我们的方法扩展到醇燃料电池。 在开发更可靠的聚合物电解质燃料电池模型时，了解燃料电池运行过程中的水分布是绝对关键的。 我们将继续使用热极化和超极化的129 NMR研究多孔材料的NMR研究。 与分子筛纳米材料CRC的Steve Kuznicki合作，我们正在使用NMR-129以及Al-27，Si-29和Ag-109 NMR来检查一些潜在重要的银交换分子筛，这些分子筛具有包括氩氧气体分离在内的应用。 最后，我们将独立工作，并与新西兰惠灵顿的维多利亚大学的Paul Callaghan合作，开发NMR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.