Structure/property relationships of active sites in crystals, amorphous materials and liquids

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Magnetic properties of materials of significant interest in biology, medicine, and industry will be studied by electron magnetic resonance techniques (also referrred to as EMR/EPR/ESR) , using paramagnetic centres as probes at active sites in these materials. [This technique is based on the same principle as that of MRI (Magetic Resonance Imaging) technique used in the hospitals.] The samples to be investigated are (i) single crystals, useful as phosphors, and replacement for silicon dioxide gate dielectrics;(ii) amorphous materials in nano-structure state: Dilute magnetic semiconductors (DMS) to be used to develop spintronic devices where the charge and spin configuration can be manipulated. The oxide semiconductor DMS doped by cobalt and iron ions are among the most promising host systems. Pulsed EMR techniques [double quantum coherence (DQC), double electron-electron resonance (DEER), and electron-electron double resonance (ELDOR)] will be exploited computationally to develop the theory to measure distances in biological systems, e.g. membranes, a cutting-edge research, not possible with the X-ray technique. The objectives will be: (1) to develop materials suitable as lasers, phosphors, and materials to be used as replacement for silicon dioxide gate dielectrics. (2) to develop DMS samples as spintronic devices. (3) The bilabelled proteins project involving 2D-ELDOR and DQC/DEER techniques would lead to distance measurements in biological systems, such as membranes, a topic providing clues into blueprints of life in the human genome project. Another related project proposed to be investigated is magnetic characterization of poly-nitroxides for use as MRI and EPRI (EPR Imaging) contrast agents, magnetic rulers and quantum cubits, leading to quantum computing.