Research objectives and content
Transition metal ions play an integral part in catalysing a variety of biological processes, principally due to the numerous oxidation states accessible to an individual ion. The importance of controlled electron transfer is exemplified by the metabolism of two simple diatomic molecules, dinitrogen and dioxygen. The presence of strong multiple bonds in both molecules presents a considerable kinetic barrier to reactivity, and at ambient temperatures and pressures both are relatively stable. The metalloenzymes involved in the reduction of these two molecules must therefore reduce these barriers significantly, and I propose to use approximate density functional theory to study the mechanisms of these fundamental processes. The research will examine the dissociation of dinitrogen and dioxygen on a variety of metal clusters, in an attempt to model the behaviour of the biological systems. The major advance in relation to previous work will be the use of the broken-symmetry approach, in which all symmetry elements connecting the two dissociationg atoms are removed, thereby allowing electrons to localise on one side or the other as the bond breaks. When located at appropriate points in space, high-spin transition metal ions may be able to stabilise the developing spin density, and hence significantly reduce the activation barrier. Training content (objective, benefit and expected impact)
Professor Eisenstein has an established reputation in many aspects of inorganic quantum chemistry, and a well-equipped laboratory with extensive computational facilities. She has also recently commenced collaboration with research groups involved in experimental aspects of bioinorganic chemistry (Dr. Parahia, Orsay). The balance of computational and experimental expertise available in the two| laboratories presents a great opportunity to develop my skills, using both the density functional theory with which I am familiar and also other computational techniques. Furthermore, collaboration with experimentalists will enable me to develop a broader understanding of the field, and will also help direct the research towards the goal of understanding bioinorganic reaction mechanisms on an electronic basis.
Links with industry / industrial relevance (22)