Computational Modeling of Spin-bearing Metal-organics and of Correlated f-Electron Systems
||Computational Modeling of Spin-bearing Metal-organics and of Correlated f-Electron Systems |
||Peter Oppeneer <email@example.com>|
||2014-07-01 – 2015-07-01|
||10304 10302 10404|
The access to excellent computer resources has become a key ingredient in modern materials research. In the present proposal we are asking for computer time for two research areas in which we are currently working, which have proven to be the most computationally demanding areas of our research.
In the first area we employ state-of-the-art calculations to study the electronic structure, magnetic and structural properties of spin-bearing metal-organic materials and single molecule magnets. Our focus is on large metal-organic molecules, which are well known from life science (for example, the Fe-porphyrin molecule that provides the functionality of hemoglobin). The magnetic properties of such molecules are very interesting. Under properly tuned conditions, spin switching of these molecules can be externally stimulated, which offers the possibility to develop versatile spintronic devices on the basis of metal-organic molecules. We are investigating the possible spin switching of metallo-porphyrins on a metallic surface and in contact with a reagent (e.g., nitric oxide) in order to discover conditions under which the spin can be switched in a molecular electronic device. An emerging research direction is that of single molecule magnets grafted to a magnetic substrate.
In the second area of our research, we perform materials modeling for nuclear fuel materials, nuclear waste, and for correlated f-electron systems. Our focus is currently moving to predicting the thermal properties of nuclear fuel materials. To predict these from first-principles we have performed simulations of the lattice dynamics (phonons) and surface vibrations. The interaction of water with the fuel material is highly relevant for the envisaged Swedish underground storage. Another important issue in the long-term storage of nuclear waste is the building up of radioactive decay defects. Investigations of irradiated nuclear fuel materials however demand special safety requirements, which can only be met at highly specialized facilities. But computational modeling has proven to be a viable, alternative route within materials research. We have investigated the the influence of oxidation on the nuclear fuel material, the thermal lattice expansion, and its reactions at the surface. Accumulation of He and Xe in the material can destroy the nuclear fuel material and even the steel containers. The modeling of such processes is computationally demanding.