EPR characterization of molecular magneto-structural correlations under pressure

Molecular magnetism represents a multidisciplinary research field focused on the employment of molecular approaches to design, create, study and use new classes of magnetic materials in which properties can be tuned at the molecular level. This project will examine the effects of pressure on molecular clusters (molecular nanomagnets) ranging from simple monomers and dimers, to complex polymetallic molecules. The use of pressure offers the potential to provide detailed information concerning the relationship between structure and magnetic properties within the same molecule, i.e. how do changes in bond lengths and angles change the way unpaired electrons on neighbouring metal ions communicate with each other? To date the only published studies of polymetallic systems under pressure involve the prototype single-molecule magnet (SMM) [Mn12], a [Mn4] cubane, and a hexametallic [Mn6]-oxime complex made by us. Although clear changes in magnetic properties are observed in all cases, the proposed explanations for the former two are somewhat speculative since they do not involve structural studies. The Edinburgh group were the first to combine high pressure magnetometry and crystallography, establishing clear magneto-structural correlations (MSCs) as a function of pressure for one member of the Mn6 family.This project aims to combine these world-leading structural and magnetic characterization techniques with (for the very first time) high pressure High-Frequency Electron Paramagnetic Resonance (HFEPR), a technique developed at the NHMFL in Tallahassee, to afford unprecedented and detailed insight into the structure-property relationship of paramagnetic materials.