Final Report Summary - UCHEM (Frontier Non-Aqueous Uranium Chemistry: Structure, Bonding, Reactivity, and Nanomagnetism)
From a historical perspective, the chemistry of uranium can be considered to lag behind the rest of the periodic table because the rarity and perceived handling problems have restricted or discouraged its use. This is particularly surprising when the fact that uranium plays a central role in nuclear power is appreciated. Notwithstanding this though, there are enduring questions regarding how uranium undertakes chemical bonding to other elements and what effect this has on reactivity. The extent of covalency in uranium bonding, that is sharing of electrons, is poorly understood, but could be key to resolving nuclear waste problems since only a small fraction of the volume of nuclear waste is actually radioactive, but separating it is difficult.
The only way to overcome the limitations on our knowledge and understanding is to prepare families of uranium and thorium molecules and study their properties in-depth. Our principal tool to achieve this is to study compounds where uranium exhibits a multiple bond to a ligand, but we also study the reactivity and magnetism of these complexes. Particularly important to our approach, is the systematic development of families of structurally related molecules and their comprehensive interrogation by a battery of techniques. Only by combining these two aspects can we deliver the breadth and depth of knowledge that we need to drive our platform of understanding to the level it needs to be at.
We have prepared many new compounds and gained important data and analysis, which has lead to a higher platform of knowledge and understanding. We have prepared many examples of uranium-ligand multiple bonds, many of which have been landmark targets for the whole community that are becoming textbook examples. We have studied the electronic structure of these new compounds with state-of-the-art methods, which has provided quantification where before qualitative models were the norm. We have uncovered new synthetic methods in the area, or adapted existing methods into this area for the first time. We have discovered new types of reactivity that often have broken new ground in the wider context as well as being new to actinide chemistry. We have also understood new magnetic phenomena and build understanding in this complex and poorly understood area. These studies have allowed us to question and reappraise several underpinning concepts in actinide chemistry more broadly, and in several instances have revealed that some concepts thought to be niche are in fact general, which is reshaping our view of the chemistry of actinide elements. Our results have been published in around 60 publications and another 20 will emerge from this project. We have disseminated our work at leading international conferences, and this has proven to be an excellent training ground for ECR PDRAs and PhDs, producing new researchers in an acknowledged skills-shortage area.
The only way to overcome the limitations on our knowledge and understanding is to prepare families of uranium and thorium molecules and study their properties in-depth. Our principal tool to achieve this is to study compounds where uranium exhibits a multiple bond to a ligand, but we also study the reactivity and magnetism of these complexes. Particularly important to our approach, is the systematic development of families of structurally related molecules and their comprehensive interrogation by a battery of techniques. Only by combining these two aspects can we deliver the breadth and depth of knowledge that we need to drive our platform of understanding to the level it needs to be at.
We have prepared many new compounds and gained important data and analysis, which has lead to a higher platform of knowledge and understanding. We have prepared many examples of uranium-ligand multiple bonds, many of which have been landmark targets for the whole community that are becoming textbook examples. We have studied the electronic structure of these new compounds with state-of-the-art methods, which has provided quantification where before qualitative models were the norm. We have uncovered new synthetic methods in the area, or adapted existing methods into this area for the first time. We have discovered new types of reactivity that often have broken new ground in the wider context as well as being new to actinide chemistry. We have also understood new magnetic phenomena and build understanding in this complex and poorly understood area. These studies have allowed us to question and reappraise several underpinning concepts in actinide chemistry more broadly, and in several instances have revealed that some concepts thought to be niche are in fact general, which is reshaping our view of the chemistry of actinide elements. Our results have been published in around 60 publications and another 20 will emerge from this project. We have disseminated our work at leading international conferences, and this has proven to be an excellent training ground for ECR PDRAs and PhDs, producing new researchers in an acknowledged skills-shortage area.