National Crystallography Service 2006 Renewal

国家晶体学服务中心 2006 年续展

• 批准号: EP/D07911X/1
• 负责人: Michael Hursthouse
• 金额: $ 158.34万
• 依托单位: University of Southampton
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FD07911X%2F1
• 关键词: National; Crystallography; Service; 2006; Renewal

X-ray crystallography is the term used to describe the use of X-ray diffraction from a crystalline sample to obtain a picture of the internal structure of the crystal at the atomic level. Crystal structures are formed when the component atoms or molecules assemble into a closely packed array that has a repeating pattern in three dimensions. X-rays have a wavelength that is of the same order of magnitude as the spacings in the repeating crystal structure pattern, and are scattered by the electron cloud of the atoms. The combination of the atomic scattering and the repeating pattern produces diffraction, in which specific diffracted beams are emitted in a finite number of well-defined directions. If the directions and intensities of these diffracted beams are recorded, using an X-ray detector, it is possible to use a computer program that simulates the actions of an optical microscope to generate an image of the electron density distribution in the crystal structure, and thus allows us to identify the structure of molecules in the solid state. This technique was first introduced in the early part of the 20th century, and it has undergone many changes and improvements. Fundamental in the development of the technique has been improvement in the power of X-ray generation, in the technology of diffracted X-ray detection, and in the computer software used for processing the diffraction data and computing the image of the crystal structure. As these technologies developed, the power of the technique has improved enormously, but so has the cost. However, with high intensities, it is possible to shorten the time taken for one experiment, and with such highly productive sources it became logical to share them, and support many users who had produced crystals and needed to confirm or to know what the structure of the compound was. Accordingly, a shared facility for UK academic chemists was created in 1981, and this has been operating as a National Service since that time. The brief of the Service was to identify, acquire and operate the latest X-ray diffraction technology and make it available to users in other institutions. A major development was introduced in 2001, when access to the single crystal facility, Station 9.8, at the Daresbury Synchroton was integrated into the Service operation. This provides an incredibly high brightness X-ray beam, making it possible to study single crystals of only a few microns in size, equivalent to individual grains of a powder.For use of both the laboratory source at Southampton, and the synchrotron source, extension of the capability offered by the joint service has been possible, via the use of still developing software that can process data and resolve structures from very poor quality crystals / either with inherent growth defects or through damage due to their soft and squidgy nature. Success in handling these types of crystal, which are increasing in number, as chemists synthesise larger and more complex, fluffy molecules is crucial to the development of the chemistry of materials of current focus, and an understanding of their chemical and physical properties. The National Crystallography Service also brings together particular expertise in dealing with difficult samples that can not be investigated successfully elsewhere in the UK.

x射线晶体学是一个术语，用来描述利用x射线衍射从晶体样品中获得晶体在原子水平上的内部结构的图像。当组成原子或分子在三维空间中以重复的模式紧密排列时，就形成了晶体结构。x射线的波长与重复晶体结构模式中的间隔具有相同的数量级，并被原子的电子云散射。原子散射和重复模式的结合产生了衍射，其中特定的衍射光束在有限数量的明确定义的方向上发射。如果使用x射线探测器记录下这些衍射光束的方向和强度，就有可能使用计算机程序模拟光学显微镜的作用来生成晶体结构中电子密度分布的图像，从而使我们能够识别固态分子的结构。这项技术最初是在20世纪早期引入的，它经历了许多变化和改进。该技术发展的基础是x射线产生功率的提高，衍射x射线探测技术的改进，以及用于处理衍射数据和计算晶体结构图像的计算机软件的改进。随着这些技术的发展，技术的能力有了很大的提高，但成本也有了很大的提高。然而，在高强度的情况下，有可能缩短一次实验所需的时间，并且有了如此高产的资源，分享它们变得合乎逻辑，并支持许多生产晶体并需要确认或知道化合物结构的用户。因此，1981年为英国学术化学家创建了一个共享设施，从那时起，这个设施一直作为国家服务机构运作。事务处的任务是查明、取得和使用最新的x射线衍射技术，并将其提供给其他机构的用户。2001年引入了一项重大发展，当访问达斯伯里同步加速器的单晶设施9.8站时，被整合到服务操作中。这提供了令人难以置信的高亮度x射线束，使得研究只有几微米大小的单晶成为可能，相当于粉末的单个颗粒。对于南安普顿的实验室源和同步加速器源的使用，通过使用仍在开发的软件，可以处理数据并解决质量非常差的晶体/固有生长缺陷或由于其柔软和粘糊糊的性质而损坏的结构，可以扩展联合服务提供的能力。随着化学家合成更大、更复杂、蓬松的分子，成功处理这类晶体的数量正在增加，这对当前关注的材料的化学发展以及对它们的化学和物理性质的理解至关重要。国家晶体学服务还汇集了处理在英国其他地方无法成功调查的困难样品的特殊专业知识。