Calixarenes: Metal-Organic Frameworks and Discrete Superstructure

Polynuclear cages of paramagnetic transition metal ions can exhibit fascinating physical properties and have great potential in the field of single molecule magnetism and molecular spintronics. Supramolecular chemistry is defined as chemistry beyond the molecule, and involves (amongst other things) the design of molecular building blocks for the construction of novel structures that can be polymeric or discrete in nature. We recently discovered a range of new polynuclear cages that have interesting magnetic properties and that act as Single-Molecule Magnets or Molecular Refrigerants (molecules that cool themselves down when a magnetic field is applied to the material). We intend to marry these cluster types with new and large scale molecular building blocks to afford novel discrete and polymeric superstructures. The resulting materials will have tailored magnetic properties (depending on the cluster type we choose to incorporate) and we will explore the ability of these assemblies to play host to guest molecules (e.g. by the passage of molecules through pores in infinite structures containing voids, or in individual cavity containing molecules). The storage and separation of important gases within all of the materials to be synthesised (either organic or metal-organic) will be studied in collaboration with Prof. Andrew Cooper, head of the Centre for Materials Discovery at the University of Liverpool.Dr. Scott J. Dalgarno has expertise in calixarene synthesis and crystallographic studies on large supramolecular polynuclear metal cluster systems. Dr. Euan K. Brechin is a world leader in molecular magnetism and polynuclear metal cluster synthesis. These synthetic and analytical techniques will be critical in elucidating the structures and properties of the materials to be formed, and have already allowed us to determine the magnetic properties of the aforementioned metal clusters that display Single-Molecule Magnet or Molecular Refrigerant behaviour to underpin the work proposed here.

The fundamental nature of this work renders the realisation of the most important longer-term applications difficult, but significant short-term benefit can be realised and is addressed below with respect to different sectors. Who will benefit from this research? How will they benefit from this research? Education and Training: The PDRA sought will greatly benefit from training across a multi-disciplinary research project, learning various aspects of supramolecular, synthetic and coordination chemistry, molecular magnetism, X-ray diffraction, and host-guest, gas-storage and separation technology. In addition, the PDRA will also attend HWU training courses on transferrable skills and open scientific workshops and courses relating to specialist analytical techniques. All team members will be involved in contributing to the writing of peer-review publications, and this will serve as a further training / development mechanism for the PDRA. The PI and CoI will continue to learn aspects of advanced magnetism and crystallography respectively through collaborative knowledge exchange, and both will learn about gas storage and separation technology through collaboration with project support partner Prof. Andrew Cooper at the Centre for Materials Discovery (CMD). Industry: Although at a fundamental stage, we have links to industry through knowledge transfer arms at both HWU and UoE, as well as the CMD, all of which is discussed in section E. Applications of our research will only become apparent once we study the properties of the molecules / assemblies we propose to form. General public: Polynuclear metal clusters have great potential use in nanotechnology applications such as data storage, molecular refrigeration and molecular spintronics. Although the proposed research is fundamental, these features, coupled with the potential to form novel host-guest assemblies / structures, could benefit the public in the longer term by contributing to the economy through the subsequent design / use of these systems. In addition to this, both the PI and CoI make positive contributions to outreach programmes through their respective institutions, and this will continue with a view to broadcasting the merit of this work and science as a whole to future generations of scientists. What will be done to ensure that they benefit from this research? Education and Training: Management of the project by both the PI and CoI will ensure that research targets are met and that the PDRA is exposed to all areas mentioned above. Training in transferrable skills will be available from the Educational Development Unit at HWU, who provide regularly scheduled courses that are pitched at appropriate levels, that bring in external experts, and that span all relevant areas. Regular contact (e.g. through conference calls, meetings and informal discussions) with collaborators on a whole will ensure that the project proceeds to time, and that all parties benefit through knowledge exchange. Industry: Regular progress discussions between the PI and CoI (either informal or in joint group meetings), as well as with collaborators, project support partners and knowledge transfer arms at HWU and UoE, will all be used to identify potential sources of exploitation and benefit to the economy. Once identified, we will approach potential industrial partners through these industrial links. General public: The application of these materials in order to benefit the public will depend on research developments. Although this is the case, we will use our proximity, collaborators and support partner, along with links to industry to maximise the likelihood of benefit to the public (described further below).Current outreach activities will continue and will develop to include topics related to the research outlined in the Case for Support as advances are made.