An X-ray Diffractometer for Extreme Conditions Research

我们感兴趣的是压力对分子固体的影响.在有机材料中，压力改变和重排分子间的接触，如氢键和货车范德华接触，导致丰富的多态性多样性。因此，压力是探索有机固体的结构灵活性（所谓的“能量消耗”）的非常有效的工具，这是药物开发中非常重要的因素，也为计算工作提供了有价值的数据，例如晶体结构的第一原理预测。在有机体系中，至少在10 GPa（100 000 atm）以下的压力下，基本分子键距的变化不会被观察到。相比之下，金属配位化合物的研究表明，与有机体系不同，分子内金属-配体键合可以受到压力的影响。这使得压力成为探索功能配位材料（如分子磁体）中结构与性能之间关系的完美工具：可以在不同的扭曲状态下研究材料，为研究结构与性能之间的相关性提供了最直接的方法。同样的方法可用于研究金属、矿物和其他延伸材料，以显示例如岩石如何在行星内部改变其结构，如何为先进技术应用而改变材料，以及材料如何在爆炸冲击波的影响下改变结构，以及如何通过控制添加剂对现代发动机极端条件的反应来提高运输效率。可以使用金刚石压砧单元对样品施加压力，其中样品保持在两个金刚石的面之间。当负载施加到金刚石上时，可以在样品处产生数千倍于大气压的压力。然后可以使用单晶X射线衍射来研究样品，这是获得原子尺度结构信息的最精确和最方便的方法，以揭示材料对压力的反应。在这个项目中，我们寻求资助一台衍射仪，使这些研究能够在极端条件下的科学中心进行，爱丁堡大学的一个致力于极端条件研究的研究所。新仪器将配备最先进的探测器和X射线源，使数据能够非常快速但高精度地收集。我们将设计和建造新的压力传感器，使数据能够在高压和变温条件下同时获得。新设施将使更复杂的超分子材料进行研究比迄今为止是可能的。这些设备的组合将提供一种独特的仪器，它能够改变温度和压力这两个基本重要的热力学变量，以深入了解固体材料中控制相稳定性的因素。

We are interested in the effect of pressure on molecular solids. In organic materials pressure modifies and rearranges intermolecular contacts such as hydrogen bonds and van der Waals contacts leading to rich polymorphic diversity. Pressure is thus a very effective tool for exploring the structural flexibility, the so-called 'energy landscapes', of organic solids, a very important factor in the development of pharmaceuticals, which also provides valuable data for computational work such as first-principals prediction of crystal structures. Changes in primary molecular bond distances tend not to be observed in organic systems at least up to 10 GPa (100 000 atm). By contrast, work on metal coordination compounds has revealed that, unlike organic systems, intramolecular metal-ligand bonding can be affected by pressure. This makes pressure a perfect tool for exploring the relationship between structure and properties in functional coordination materials such as molecular magnets: a material can be studied in different states of distortion, providing the most direct way to study correlations between structure and properties. The same methodology can be used to study metals, minerals and other extended materials, to show, for example, how rocks change their structures in planetary interiors, how materials can be modified for advanced technological applications and how materials change structure under the influence of shock waves during detonations, and how transport can be made more efficient by controlling the response of additives to the extreme conditions of modern engines. Pressure can be applied to a sample using a diamond anvil cell, in which a sample is held between the faces of two diamonds. When load is applied to the diamonds, pressure many thousands of times atmospheric pressure can be generated at the sample. The sample can then be studied using single-crystal X-ray diffraction, which is the most precise and convenient way to obtain structural information on the atomic scale, to reveal how the material responds to pressure.In this project we seek funding for a diffractometer that will enable these studies to be carried out at The Centre for Science at Extreme Conditions, an institute dedicated to extreme conditions research at The University of Edinburgh. The new instrument will be equipped with state-of-the-art detector and X-ray sources, to enable data to be collected very quickly but with high precision. We will design and build new pressure cells which will enable data to be obtained simultaneously at high pressure and variable temperature. The new facility will enable much more complex supramolecular materials to be studied than has hitherto been possible. The combination of these facilities will provide a unique instrument which enables variation of two fundamentally important thermodynamic variables of temperature and pressure to provide deep insight into the factors which govern phase stability in solid materials.