A National Electron Diffraction Facility for Nanomaterial Structural Studies

电子衍射（艾德）即将成为一种定量技术，将常规用于解决和细化晶体结构从非常小的标本。这些材料最多也就是难以用X射线衍射（XRD）来处理，而且许多材料完全超出了目前的能力范围。电子散射的物理性质非常不同，这意味着可以解决晶粒尺寸小于1微米的晶体结构，以及含有氢和锂等轻元素的材料。通过将目前用于XRD的方法和检测器（经过数十年的发展）提升到高水平，并将其与专用电子衍射仪相结合，可以实现这一飞跃。由此产生的设备允许对纳米材料进行常规分析。这项新技术打开了许多大门，在某些领域节省了几个月的结晶和晶体生长工作。电子衍射本身并不是什么新鲜事，但在对这些测量产生的数据进行建模时，需要考虑使其超越XRD的因素，特别是多重散射。这在很大程度上仍是一项正在进行的工作，必须弥合学科之间的差距，引入电子显微镜的知识和方法，以充分发挥该方法的潜力。这些机器仅在去年才开始商业化。为了保持在结构科学领域的竞争力，英国必须在这一领域进行投资，并通过迅速这样做来引领全球。对于英国研究人员来说，这种新能力的最大好处将是由一个国家艾德设施提供，该设施具有开发这种新生技术的能力和专业知识，可用于常规和广泛使用。南安普顿大学（UoS）的国家晶体学服务（NCS）处于提供这种设施的有利位置，利用大多数研究人员在其本国机构无法获得的高价值设备，成功地定期提供结构解决方案和改进。沃里克大学（UoW）拥有全国领先的电子显微镜和XRD设备，在提供多用户访问方面取得了成功。UoW在建模和开发艾德技术方面也处于领先地位，并带来了一套方法（低温支架、加热支架、基于MEMS的原位支架、氧化石墨烯支撑膜），将艾德的能力扩展到新的领域。UoS和UoW将共同提供一个双站点，单一的国家设施，将建立在现有的世界一流的实验室基础设施上，立即在国家和地方规模上提供技术，并开发未来的方法，以利用英国的这一机会。无机材料和分子固体。工业界，特别是制药业，意识到艾德的影响，并强烈表达了对该技术的需求。因此，学术界和工业界都强烈支持拟议的设施，英国这些社区的主要代表已同意成立一个独立的艾德工作组，并作为倡导者推广该方法和设施。为了了解艾德应如何发展，使能力和能力与英国科学界的需求相匹配，工作组和UoS/UoW团队将进行一项与NCS国家访问周期相一致的景观设计工作。这将使新的社区被识别和援助战略明智的投资，以提高英国的能力和研究在原子结构测定的基本和必要的领域。这个设施的时机是理想的，因为艾德技术现在成为可用的研究社区的要求，它的大片对齐。

Electron diffraction (ED) is about to become a quantitative technique that will be used routinely to solve and refine crystal structures from extremely small specimens. These materials are, at best, difficult to tackle with X-ray diffraction (XRD) and many are completely beyond the reach of current capabilities. The very different physics of electron scattering means that structures of crystals with grain sizes smaller than a micrometre, and materials containing light elements like hydrogen and lithium, can be solved.This step-change will be made possible by taking the methods and detectors currently used for XRD, which have been developed over decades to a high level, and combining them with a purpose-built electron diffractometer. The resulting equipment allows routine analysis of nanoscale materials. This new technology opens many doors, in some fields saving months of work in crystallisation and crystal growth. Unsurprisingly, there is intense interest both on a national and international level.Electron diffraction itself is not new, but the factors that allow it to reach beyond XRD, particularly multiple scattering, need to be considered when modelling the data produced in these measurements. This is still very much a work in progress, and it will be essential to bridge the gap between disciplines, bringing in knowledge and methods from electron microscopy, to develop the method to its full potential.These machines have become commercially available only in the last year. To remain competitive in structural science, the UK must invest in this area, and can take a global lead by doing so promptly. The widest benefit of this new capability for UK researchers will be provided by a national facility for ED that has both capacity and expertise to develop this nascent technology for routine and widespread use.The National Crystallography Service (NCS) at the University of Southampton (UoS) is well-placed to deliver such a facility, building on its success in routinely providing structure solution and refinement using high-value equipment that is unavailable to most researchers in their home institutions. The University of Warwick (UoW) has nationally leading electron microscopy and XRD facilities with a proven success in offering multiuser access. UoW also has a leading position in modelling and developing ED techniques and brings a suite of methods (cryogenic holders, heating holders, MEMS-based in-situ holders, graphene oxide support films) that will extend ED capabilities into new areas. Together, UoS and UoW will provide a dual site, single national facility that will build on existing world class lab infrastructure, deliver the technique immediately at both national and local scale, and develop the method going forward to take advantage of this opportunity for the UK.Four areas are identified as having the most to gain immediately from new ED techniques: pharmaceuticals; metal-organic frameworks; inorganic materials and molecular solids. Industry, in particular Pharma, realises the impact of ED and is keenly expressing a need for access to the technique.There is therefore strong support for the proposed facility from both academia and industry, and leading representatives from these communities in the UK have agreed to form an independent ED working group and act as champions to promote the method and facility. To understand how ED should develop, matching capacity and capabilities to the needs of the UK science community, the working group and the UoS/UoW team will undertake a landscaping exercise that will align with NCS national access cycles. This will allow new communities to be identified and aid strategically informed investment to grow UK capacity and research in the fundamental and essential area of atomic structure determination.The timing for this facility is ideal as ED technology now becoming available aligns with swathes of research communities demanding it.