High-Resolution SEDOR and Switch Angle Sample Spinning Probes for Dipolar Recoupling

用于偶极重耦合的高分辨率 SEDOR 和开关角样品旋转探针

• 批准号: 0846583
• 负责人: Terry Gullion
• 金额: $ 42万
• 依托单位: West Virginia University Research Corporation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0846583&HistoricalAwards=false
• 关键词: Resolution; SEDOR; Switch; Angle; Sample

The overarching goal of this proposal is the development of new techniques for structure elucidation in the solid state. The PI proposes to accomplish this by exploiting dipolar couplings between nuclear spins. The strength of these couplings correlates with interatomic distances and thus provides structural information that is otherwise only accessible by diffraction techniques. The advantages of using nuclear magnetic resonance (NMR) over diffraction lie in the fact that single crystals are not required, and that the method is very sensitive to protons which are usually invisible in X-ray diffraction experiments. The PI pioneered this technique for nuclei with nuclear spin of 1/2 (such as H, C, F, P). In this proposal, the PI seeks to expand this technique to quadrupolar nuclei with a spin greater or equal than 1. In fact, most of the elements in the periodic table possess magnetically active isotopes only with quadrupolar spin. Many of these are extremely important for biological samples (Na, O) or materials research (Li, Cs, V, etc.) The PI proposes the design and construction of new NMR probes and their implementation in a series of new NMR experiments to achieve this goal. Structure elucidation is one of the central questions in chemistry. The understanding of molecular structure helps to deduce relationships with molecular function. This knowledge is crucial for the development of new materials that enhance the quality of our lives or allow for the creation of new drugs. Structure elucidation of materials in their solid state using diffraction techniques usually requires the material to be present in their crystalline, or well-ordered, form. However, especially biological materials are often difficult to crystallize and thus tools like nuclear magnetic resonance (NMR) spectrocopy have been developed to aid in structure elucidation. NMR spectroscopy has other limitations, however, such as a much lower sensitivity, and generally, the inaccessibility of elements whose nuclei suffer from a non-spherical charge distribution. The majority of elements in the periodic table falls into this category, and includes elements of high biological relevance such as oxygen and sodium. The latter are inaccessible to atomic distance measurements by solid state NMR. Professor Gullion from West Virginia University plans to design, develop and build new instruments that will allow NMR measurements on these ubiquitous and important elements. Professor Gullion will engage the help of undergraduate, graduate, and postdoctoral students in this endeavor. He will share his technical know-how via video clips disseminated over the web, and free workshops in his laboratory. He will continue to entice our youngest generation about science through magic shows performed at the kindergarten level.

该提案的总体目标是开发固态结构阐明的新技术。 PI 建议通过利用核自旋之间的偶极耦合来实现这一目标。这些耦合的强度与原子间距离相关，因此提供了只能通过衍射技术才能获得的结构信息。使用核磁共振 (NMR) 相对于衍射的优点在于不需要单晶，并且该方法对 X 射线衍射实验中通常不可见的质子非常敏感。 PI 首创了针对核自旋为 1/2 的核（例如 H、C、F、P）的这项技术。在该提案中，PI 试图将该技术扩展到自旋大于或等于 1 的四极核。事实上，元素周期表中的大多数元素仅具有四极自旋的磁活性同位素。其中许多对于生物样品（Na、O）或材料研究（Li、Cs、V 等）极其重要。PI 提议设计和构建新的 NMR 探针，并在一系列新的 NMR 实验中实施以实现这一目标。结构解析是化学的核心问题之一。对分子结构的理解有助于推断与分子功能的关系。这些知识对于开发提高我们生活质量或创造新药物的新材料至关重要。使用衍射技术对固态材料进行结构解析通常要求材料以晶体或有序的形式存在。然而，尤其是生物材料通常难以结晶，因此核磁共振 (NMR) 光谱等工具已被开发出来以帮助结构阐明。然而，核磁共振波谱还有其他局限性，例如灵敏度低得多，并且通常难以接近其核具有非球形电荷分布的元素。元素周期表中的大多数元素都属于这一类，其中包括具有高度生物相关性的元素，例如氧和钠。后者无法通过固态核磁共振进行原子距离测量。西弗吉尼亚大学的 Gullion 教授计划设计、开发和制造新仪器，以便对这些普遍存在的重要元素进行核磁共振测量。 Gullion 教授将在本科生、研究生和博士后的帮助下完成这项工作。他将通过网络上传播的视频剪辑以及实验室内的免费研讨会来分享他的技术知识。他将继续通过幼儿园级别的魔术表演来吸引我们最年轻的一代了解科学。