Core Capability for Chemistry Research - Leeds

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In Part A of our Bid, the School of Chemistry, University of Leeds requests funds to purchase a 600 MHz NMR Spectrometer, a Single Crystal XRD Spectrometer and a Variable Pressure SEM.The 600 MHz NMR Spectrometer will replace the main service instrument in the School, which is used by 75% of the academic staff. The new instrument will have low and high (variable) temperature and multinuclear capability (including 11B) and is employed for more complex analyses, including selective excitation experiments, more 'exotic' nuclei detection, dynamics studies, and for (very) sample limited data collections. It will also provide increased resolution as compared with the existing instrument and a shielded (high cryogen hold time) magnet and new probes will provide greatly improved signal-to-noise characteristics for all nuclei. The spectrometer will primarily be used to provide the School service, but its superior performance as compared with our old instrument means that the facility can also be opened up to less experienced users for specialist applications. The new single crystal diffractometer system will replace a failing 10 year old instrument and will support the work of approximately 50% of the academic staff in the department, providing vital access to structural determination. The instrument will have a microfocus X-ray source that has dual wavelength (Mo and Cu) capacity, along with peripheral equipment such as a cryogenic crystal cooling unit and server for raw data storage and backup. The new system will have enhanced and expanded capabilities in comparison with our current set-up through improved power and sensitivity, and the ability to determine absolute configuration of light-atom samples which we cannot currently do. A variable pressure FEG-SEM with integral EDX (energy-dispersive X-ray spectroscopy) will provide new capability and will enable high resolution imaging and elemental analysis of solid samples at the nanometer level. The instrument will be equipped with a temperature-control stage, and we will also purchase software enabling automated analysis of multiple samples. In addition, it will have multiple ports which will permit interfacing with further analytical tools (such as atomic force microscopy (AFM)). That the instrument can be operated from high to low vacuum provides maximum flexibility, allowing analysis of both conducting and non-conducting samples. We also need to purchase a metal coating unit to coat larger, non-conducting samples which can be prone to charging. The request of a variable pressure FEG-SEM reflects the changing landscape of chemistry research in the UK. While chemistry departments have not traditionally housed electron microscopes, as research areas such as materials chemistry continue to grow in importance, and the specification of microscopes continues to improve, it is essential that researchers have ready access to high specification instruments.Part B of the proposal makes the case for establishment of a centre for "High Resolution Analytical Transmission Electron Microscopy (TEM) of Beam Sensitive Materials" with purchase of a state-of-the-art Titan Krios cryo-electron TEM which combines high resolution 2D imaging with electron tomography and advanced analytical techniques (electron energy loss spectroscopy (EELS) and electron diffraction). This instrument makes it possible for the first time to look at dose-sensitive structures with such high resolution that atomic imaging of soft matter becomes a reality. In Part B we also request new capability with the purchase of a liquid cell holder for a TEM, and an AFM to integrate with the SEM purchased in Part A. A powder XRD will also bring new capability to the school. Finally, we request a LC-MS(MS) mass spectrometer to replace our workhorse, user-operated instrument and a 600 MHz instrument, equipped with a cold probe which will replace an existing instrument and bring new resolution capabilities.