Advanced applications of SXD in structural evolution in molecular systems, and towards chemical applications of LMX

SXD 在分子系统结构演化以及 LMX 化学应用中的高级应用

• 批准号: EP/F021666/1
• 负责人: Charles Wilson
• 金额: $ 16.37万
• 依托单位: University of Glasgow
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2007
• 资助国家: 英国
• 起止时间: 2007 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FF021666%2F1
• 关键词: Advanced; applications; SXD; structural; evolution

We are interested in the way molecules hold together in the solid state. This can happen by various favourable interactions, but the one we are most interested in is hydrogen bonding, which is amongst the strongest of these intermolecular interactions. The methods we use to carry out these studies are diffraction and computational chemistry. The diffraction - a way of elucidating molecular structure inside crystalline materials - is carried out using both X-rays (routine in the home laboratory) and neutrons (only available at central facilities). The work we propose to do here focuses on diffraction studies, and includes a particular emphasis on neutron diffraction. Neutron diffraction is important in our work as it gives the definitive means of locating the important hydrogen atoms in our molecular structures (X-rays are much less good at this in general). Since we are interested in the intermolecular hydrogen bonds and their detailed behaviour, and since hydrogen atoms are vital to the formation and understanding of hydrogen bonds, the need for neutron diffraction in our work is clear.Over many years we have carried out an extensive programme of research exploiting variable temperature single crystal diffraction measurements, with a particular emphasis on applying neutron diffraction methods to the study of hydrogen atom behaviour in molecular systems. We look for odd or interesting behaviour of the hydrogen atoms, including situations where they may be mobile (proton transfer) or otherwise able to be tuned within hydrogen bonds - if we can tune the nature of hydrogen bonds we can exert a lot of control over the properties of materials, even including changing their colour, or electrical properties, etc. In parallel with this, the architecture of the structures we create using hydrogen bonds can have useful properties in themselves, such as cavities, and part of our work involves trying to create molecular materials with cavities and then trying to put gases in and out of these, with many potential applications. None of this is easy to do - the structural chemistry of our systems is very flexible and does not always lend itself to precise design of the way in which molecules hold together, but we have many techniques for increasing our chances of making this happen.In the work we want to do here, we apply these neutron diffraction methods to a range of hydrogen-bonded material that have various potentially interesting features. However, since we are doing to be looking at how structures might change as the conditions are changed (for example if we heat or cool the sample, or if we apply pressure to it), this is a challenge for neutron diffraction. In fact it is only very recently that the instruments - have been capable of tackling this problem. The work we want to do on the SXD instrument at the ISIS neutron source has been made possible by pioneering advances in instrumentation and data collection techniques, which now routinely allow neutron single crystal diffraction data to be obtained in periods from a few hours to a day or so for many of the systems in which we are interested. As part of this work we will also study systems that are probably beyond the scope of even the upgraded SXD instrument, but these will provide important data and challenging targets for the LMX instrument being built on the ISIS Second Target Station.A student will work on this project, and will have the chance to work both in the home laboratory and extensively at the SXD Facility with the scientists there, to help discover some exciting science in the programme of structural science, but also gain experience of using the SXD instrument in the area of chemistry, which will be useful to chemistry beyond out own group studying these specific materials.

我们对分子在固态下结合在一起的方式感兴趣。这可以通过各种有利的相互作用来发生，但我们最感兴趣的是氢键，它是这些分子间相互作用中最强的一种。我们用于进行这些研究的方法是衍射和计算化学。衍射是一种阐明晶体材料内部分子结构的方法，它是使用 X 射线（家庭实验室中的常规操作）和中子（仅在中央设施中可用）进行的。我们建议在这里做的工作重点是衍射研究，并特别强调中子衍射。中子衍射在我们的工作中很重要，因为它提供了在分子结构中定位重要氢原子的明确方法（一般来说，X 射线在这方面不太擅长）。由于我们对分子间氢键及其详细行为感兴趣，并且氢原子对于氢键的形成和理解至关重要，因此我们的工作中对中子衍射的需求是显而易见的。多年来，我们利用变温单晶衍射测量进行了广泛的研究计划，特别强调将中子衍射方法应用于分子系统中氢原子行为的研究。我们寻找氢原子的奇怪或有趣的行为，包括它们可能是可移动的（质子转移）或能够在氢键内进行调整的情况 - 如果我们可以调整氢键的性质，我们可以对材料的特性进行很多控制，甚至包括改变它们的颜色或电特性等。与此并行，我们使用氢键创建的结构的体系结构本身可以具有有用的特性，例如空腔，以及我们的结构的一部分。 工作包括尝试制造带有空腔的分子材料，然后尝试将气体放入和取出这些材料，这具有许多潜在的应用。这一切都不容易做到——我们系统的结构化学非常灵活，并不总是适合分子结合方式的精确设计，但我们有许多技术来增加实现这一目标的机会。在我们要做的工作中，我们将这些中子衍射方法应用于一系列具有各种潜在有趣特征的氢键材料。然而，由于我们正在研究结构如何随着条件的变化而变化（例如，如果我们加热或冷却样品，或者如果我们对其施加压力），这对中子衍射来说是一个挑战。事实上，直到最近，这些仪器才能够解决这个问题。我们想要在 ISIS 中子源的 SXD 仪器上进行的工作是通过仪器和数据收集技术的开创性进步而成为可能的，现在对于我们感兴趣的许多系统来说，这些技术通常可以在几小时到一天左右的时间内获得中子单晶衍射数据。作为这项工作的一部分，我们还将研究可能超出升级后的 SXD 仪器范围的系统，但这些将为在 ISIS 第二目标站上建造的 LMX 仪器提供重要的数据和具有挑战性的目标。学生将参与该项目，并将有机会与那里的科学家一起在家庭实验室和 SXD 设施中广泛工作，以帮助发现结构科学计划中的一些令人兴奋的科学，同时也获得使用 SXD 的经验 化学领域的仪器，这对于我们研究这些特定材料的小组之外的化学很有用。

项目成果

Tuning Proton Behavior in a Ternary Molecular Complex

调节三元分子复合物中的质子行为

• DOI: 10.1021/cg100315u
• 发表时间: 2010
• 期刊: Crystal Growth & Design
• 影响因子: 3.8
• 作者: Thomas L

Engineering Short, Strong, Charge-Assisted Hydrogen Bonds in Benzoic Acid Dimers through Cocrystallization with Proton Sponge

通过与质子海绵共结晶在苯甲酸二聚体中设计短、强、电荷辅助的氢键

• DOI: 10.1021/acs.cgd.5b01787
• 发表时间: 2016
• 期刊: Crystal Growth & Design
• 影响因子: 3.8
• 作者: Thomas L

4-Phenoxyphenol: A Porous Molecular Material

• DOI: 10.1021/cg200998u
• 发表时间: 2012-04-01
• 期刊: CRYSTAL GROWTH & DESIGN
• 影响因子: 3.8
• 作者: Thomas, Lynne H.;Cheung, Elaine;Wilson, Chick C.
• 通讯作者: Wilson, Chick C.

The Effect of Local Crystalline Environment on Hydrogen Atom Behavior in Molecular Complexes of a Proton Sponge

局部晶体环境对质子海绵分子配合物中氢原子行为的影响

• DOI: 10.1021/acs.cgd.5b01788
• 发表时间: 2016
• 期刊: Crystal Growth & Design
• 影响因子: 3.8
• 作者: Jones A