X-ray spectroscopy as a probe of unique bonding interactions of importance in transition metal catalytic processes

分子如何结合在一起以及它们如何反应的细节取决于对它们的几何和电子结构的基本理解。使用光谱和计算工具的组合，我们试图提供一个详细的了解，特别感兴趣的分子，由于其独特的化学性质的电子结构。在本提案中，我们试图探索两大类分子相互作用的具体方面，以便提供一个基本框架，从中我们可以了解它们的化学行为以及它们如何用于许多化学应用。金属配合物是重要的学术和工业催化过程中常见的中间体。使用一系列的光谱方法，我们试图清楚地识别和量化的重要性-backbonding在定义这些物种的性质。我们把注意力集中在一系列的镍和铜的配合物，使我们可以利用X-射线光谱方法来量化这些物种中的键合。重要的是，我们试图将这些发现与这些物种的反应性联系起来，以便我们能够更准确地预测涉及这种类型相互作用的反应性中间体的行为。卤素键合是一类新兴的化学相互作用，广泛用于新材料的合成和传感器应用。虽然这种相互作用通常被认为是类似于更常见的氢键，我们最近已经确定，这些化学键更接近于过渡金属配位键中观察到的那些。考虑到它们的相似性，我们假设卤素键可能会与配位键竞争，产生高活性物种。因此，我们正在探索过渡金属体系中卤素键合的作用，以量化其对配位络合物的电子结构及其反应性的影响。

The specifics of how molecules are held together and how they react depends on a fundamental understanding of their geometric and electronic structure. Using a combination of spectroscopic and computational tools, we seek to provide a detailed understanding of the electronic structure of molecules that are of particular interest due to their unique chemical properties. In this proposal, we seek to explore specific aspects of two major classes of molecular interactions in order to provide a basic framework from which we can understand their chemical behaviour and how they may be used in a number of chemical applications.***Metal complexes are common intermediates in important academic and industrial catalytic processes. Using a range of spectroscopic approaches, we seek to clearly identify and quantify the importance of -backbonding in defining the nature of these species. We focus our attention on a series of nickel and copper complexes such that we may exploit x-ray spectroscopic methods to quantify the bonding in these species. Importantly, we seek to correlate these findings with the reactivity of such species so that we may be able to more accurately predict the behaviour of reactive intermediates involving interactions of this type.***Halogen bonding is an emerging class of chemical interactions that are being used extensively in the synthesis of new materials and for sensor applications. Although such interactions are typically considered to be similar to the more common hydrogen bonding, we have recently determined that these chemical bonds are closer to those observed in transition metal coordination bonds. Given their similarities, we postulate that halogen bonding may compete with coordination bonds to generate highly reactive species. We are therefore exploring the role of halogen bonding in transition metal systems to quantify its effect on both the electronic structure of coordination complexes and their reactivity.