High-Resolution Solid-State NMR in St Andrews: Development and Applications

圣安德鲁斯高分辨率固态核磁共振：开发和应用

基本信息

批准号：
EP/E041825/1
负责人：
Sharon Ashbrook
金额：
$ 157.5万
依托单位：
University of St Andrews
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2008
资助国家：
英国
起止时间：
2008 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FE041825%2F1
关键词：
Resolution Solid State NMR St

项目摘要

The proposal aims to provide modern equipment in St Andrews which will enable the development of new Nuclear Magnetic Resonance (NMR) experiments to provide insight into structure of solids. NMR spectroscopy utilises the inherent magnetism of atomic nuclei to probe the local structural and dynamic environment of a material. However, for solids the orientational dependence of many of the interactions which affect NMR spectra (and which are averaged in liquids by rapid molecular tumbling) results in large broadenings and uninformative spectra. Much work has focussed on the removal of this broadening through techniques such as magic-angle spinning (MAS) and multiple-quantum MAS (MQMAS). Recent improvements in magnet technology, hardware and methodological development have advanced solid-state NMR to the stage where it can now be employed to provide detailed information on chemically-complex systems of industrial, biological and geological relevance.We aim to use the new equipment to develop new experiments and improve existing techniques to acquire both high-resolution spectra, and provide structural information through experiments which correlate different nuclei (demonstrating, for example, the spatial proximity of two species or providing information on the nature of their chemical bonding). This type of information is a crucial step in linking the atomic scale structure of a material to its macroscopic properties. Furthermore, we will widen the applicability of these approaches to the more challenging and unusual nuclei present in many materials of industrial and commercial interest. These include nuclei with low sensitivity (89Y, 39K), low natural abundances (17O, 25Mg), long relaxation times (89Y), and larger quadrupolar couplings (45Sc, 71Ga, 93Nb) in materials where structural disorder, significant dynamic behaviour, or the presence of paramagnetic ions, for example, are a problem. The use of modern probe hardware and increased magnetic field strength will be crucial in achieving these goals.We will utilise these state-of-the-art experiments in a range of areas including 17O and 25Mg NMR of the high-pressure silicate minerals in the inner layers of the Earth, where NMR sensitivity is limited by the small amount of sample produced (typically 3-15 mg) in the high-pressure synthesis. Also we will study the local structure and ordering by 89Y, 17O and 119Sn NMR in pyrochlore ceramic materials, which have been proposed as host phases for the encapsulation and long-term storage of nuclear waste. A further area of interest is the characterisation of the local structure and geometry of microporous framework materials (through 27Al, 31P, 45Sc and 71Ga NMR), which have applications as catalysts and gas storage media.

该提案旨在在圣安德鲁斯提供现代化设备，以便开发新的核磁共振（NMR）实验，从而深入了解固体结构。核磁共振波谱利用原子核的固有磁性来探测材料的局部结构和动态环境。然而，对于固体，许多影响 NMR 谱的相互作用的方向依赖性（并且在液体中通过快速分子翻滚来平均）导致大的展宽和无信息的谱。许多工作都集中在通过魔角旋转 (MAS) 和多量子 MAS (MQMAS) 等技术来消除这种展宽。磁体技术、硬件和方法开发的最新改进已将固态核磁共振推进到现在可以用来提供与工业、生物和地质相关的化学复杂系统的详细信息的阶段。我们的目标是使用新设备开发新实验并改进现有技术来获取高分辨率光谱，并通过关联不同原子核的实验提供结构信息（例如，证明两个物种的空间接近性或提供有关其化学键性质的信息）。此类信息是将材料的原子尺度结构与其宏观特性联系起来的关键步骤。此外，我们将扩大这些方法的适用性，以应对许多具有工业和商业利益的材料中存在的更具挑战性和不寻常的原子核。这些包括在结构无序、显着动态行为或例如，顺磁性离子的存在就是一个问题。使用现代探针硬件和增强的磁场强度对于实现这些目标至关重要。我们将在一系列领域利用这些最先进的实验，包括高压硅酸盐矿物的 17O 和 25Mg NMR。地球内层，核磁共振灵敏度受到高压合成中产生的少量样品（通常为 3-15 毫克）的限制。此外，我们还将通过 89Y、17O 和 119Sn NMR 研究烧绿石陶瓷材料中的局部结构和有序性，这些陶瓷材料已被提议作为核废料封装和长期储存的主体相。另一个令人感兴趣的领域是微孔骨架材料的局部结构和几何形状的表征（通过 27Al、31P、45Sc 和 71Ga NMR），这些材料可用作催化剂和气体存储介质。