Solid-State NMR at 850 MHz: A World-leading UK Facility to deliver Advances in Materials Science, Chemistry, Biology, Earth Science and Physics

850 MHz 固态核磁共振：世界领先的英国设施，在材料科学、化学、生物学、地球科学和物理学方面取得进展

• 批准号: EP/F018096/1
• 负责人: Sharon Ashbrook
• 金额: $ 2.66万
• 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: 2009
• 资助国家: 英国
• 起止时间: 2009 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FF018096%2F1
• 关键词: Solid; State; NMR; 850; MHz

It is the structural arrangement and motion of molecules and ions that determine, e.g., the bulk properties of a material or the function of biomolecules. Therefore, the availability of state-of-the-art analytical infrastructure for probing atomic-level structure and dynamics is essential to enable advances across science. The power of solid-state Nuclear Magnetic Resonance (NMR) as such a probe is being increasingly demonstrated by applications to, e.g., materials for hydrogen storage and radioactive waste encapsulation, pharmaceutical formulations, and the amyloid plaques associated with diseases such as Alzheimer's. Solid-state NMR is most sensitive to the local chemical structure (usually up to a few bond lengths) around a particular nucleus and is thus well suited to characterising the many important systems that lack periodic order, making it complementary to well-established diffraction techniques.To extend the applicability of NMR, two key limiting factors must be addressed: sensitivity, i.e., the relative intensity of spectral peaks as compared to the noise level, and resolution, i.e., the linewidths of individual peaks that determine whether two close-together signals can be separately observed. Both sensitivity and resolution are much improved by performing NMR experiments at higher magnetic field, thus making possible applications that are not feasible at lower field. Hence, this proposal is to establish a UK facility for solid-state NMR at a world-leading magnetic field strength of 20 Tesla, corresponding to a frequency for the 1H hydrogen nucleus of 850 MHz. The resonant frequency of different nuclear isotopes are well separated such that an NMR spectrum is specific to a particular chosen isotope. NMR experiments at 20 Tesla will make use of as much of the Periodic Table as possible. A particular focus will be on nuclei which are difficult due to their low natural abundance or low resonance frequency - there are many important so-called low-gamma nuclei, e.g., 25Mg, 33S, 39K, 43Ca, 47/49Ti, with resonance frequencies < 10% of 1H. High magnetic field is especially important for the study of the over two thirds of NMR-active isotopes (i.e., with non-zero spin) that possess a quadrupolar electric moment, i.e., a non-spherical distribution of electric charge. For nuclei with spin 1/2, e.g., 13C, the routinely applied technique of physically rotating the sample around an axis inclined at the so-called magic angle of 54.7 degrees to the magnetic field direction yields narrow resonance peaks. However, for the many quadrupolar nuclei with half-integer spin, a residual broadening remains in the magic-angle spinning experiment. This residual quadrupolar broadening (in the usual NMR scale of ppm) is inversely proportional to the magnetic field squared; as well as improving resolution, the concentration of the signal intensity into a narrower lineshape hence means a still greater sensitivity dependence on the magnetic field strength. Oxygen is a key constituent of most organic and inorganic compounds; however, it is difficult to study by NMR since the only NMR-active isotope is the quadrupolar nucleus 17O, whose natural abundance is only 0.037 %. Nearly all NMR studies to date have required the preparation of 17O-labelled samples (starting with 17O-enriched water); very excitingly, working at 20 Tesla offers the possibility of recording high-resolution 17O spectra at natural abundance.A test of a powerful technique is its applicability to a wide range of problems. The high-field solid-state NMR facility will make possible experiments that provide unique information for applications across science, ranging from materials for catalysis, radioactive waste encapsulation, dental implants, batteries, drug delivery, through gaining new understanding of geological processes, to the life sciences, e.g., amyloid plaques, metal-binding proteins, bone structure, membrane proteins, enzymes.

分子和离子的结构排列和运动决定了材料的大量特性或生物分子的功能。因此，最先进的分析基础架构用于探测原子水平的结构和动力学对于能够在科学跨越的进步至关重要。固态核磁共振（NMR）的功率越来越多地通过应用于氢储存和放射性废物封装的材料，药物配方和与诸如阿尔茨海默氏症等疾病相关的淀粉样蛋白块的材料。固态NMR对特定核周围的局部化学结构（通常长达几个键长）最敏感，因此非常适合表征缺乏周期性顺序的许多重要系统，从而使其互补地与良好的衍射技术互补。即，单个峰的线宽决定了是否可以单独观察到两个近距离信号。通过在较高的磁场上进行NMR实验，从而使灵敏度和分辨率都大大提高，从而使可能的应用在较低场上不可行。因此，该建议是在20个特斯拉的世界领先磁场强度下建立一个英国固态NMR的设施，对应于850 MHz的1H氢核的频率。不同核同位素的谐振频率很好地分开，因此NMR光谱特定于特定选择的同位素。 20特斯拉的NMR实验将尽可能多地使用周期表。特定的重点将放在核上，由于其低自然丰度或低共振频率很难 - 有许多重要的所谓低伽马核，例如25mg，33s，39k，39k，43ca，47/49ti，共振频率<10％的1H。高磁场对于对具有四分之二的NMR活性同位素的研究尤其重要，即具有四极电动矩的NMR活性同位素（即具有非零自旋），即电荷的非球形分布。对于具有自旋1/2的核，例如13c，通常应用的技术在靠近磁场方向的所谓的54.7度的所谓魔法角度将样品物理旋转的轴周围旋转，从而产生狭窄的谐振峰。然而，对于许多具有半含量自旋的四极核核，魔法旋转实验中仍然存在残留的拓宽。这种残留的四极性宽扩向（在PPM的常规NMR量表中）与磁场平方成反比。除了改善分辨率外，信号强度的浓度还指向较窄的线形，因此意味着对磁场强度的灵敏度依赖性更大。氧是大多数有机和无机化合物的关键成分。但是，NMR很难研究，因为唯一的NMR活性同位素是四极核17o，其自然丰度仅为0.037％。迄今为止，几乎所有NMR研究都需要制备17O标记的样品（从17o富含水开始）；非常令人兴奋的是，在20特斯拉工作的工作提供了在自然丰度下录制高分辨率17o光谱的可能性。强大的技术测试是其适用于广泛问题的适用性。 The high-field solid-state NMR facility will make possible experiments that provide unique information for applications across science, ranging from materials for catalysis, radioactive waste encapsulation, dental implants, batteries, drug delivery, through gaining new understanding of geological processes, to the life sciences, e.g., amyloid plaques, metal-binding proteins, bone structure, membrane proteins, enzymes.

项目成果

Polymorphism, Weak Interactions and Phase Transitions in Chalcogen-Phosphorus Heterocycles.

• DOI: 10.1002/chem.201800978
• 发表时间: 2018-08-01
• 期刊: Chemistry (Weinheim an der Bergstrasse, Germany)
• 作者: Camacho PS;Stanford MW;McKay D;Dawson DM;Athukorala Arachchige KS;Cordes DB;Slawin AMZ;Woollins JD;Ashbrook SE
• 通讯作者: Ashbrook SE

Synthesis, Isotopic Enrichment, and Solid-State NMR Characterization of Zeolites Derived from the Assembly, Disassembly, Organization, Reassembly Process.

• DOI: 10.1021/jacs.7b00386
• 发表时间: 2017-04-12
• 期刊: Journal of the American Chemical Society
• 影响因子: 15
• 作者: Bignami GPM;Dawson DM;Seymour VR;Wheatley PS;Morris RE;Ashbrook SE
• 通讯作者: Ashbrook SE

A gel aging effect in the synthesis of open-framework gallium phosphates: structure solution and solid-state NMR of a large-pore, open-framework material.

• DOI: 10.1039/c7dt03709k
• 发表时间: 2017-12-12
• 期刊: Dalton transactions (Cambridge, England : 2003)
• 作者: Broom LK;Clarkson GJ;Guillou N;Hooper JE;Dawson DM;Tang CC;Ashbrook SE;Walton RI
• 通讯作者: Walton RI