Alexander Thompson

Research Interests

Using tools like Density Functional Theory and Molecular Dynamics to calculate the properties of materials in extreme environments.

Uranium dioxide has a complicated magnetic structure (collinear on left and non-collinear on right) as well as a distortion in the oxygen sublattice.

Current Research

Nuclear fuels like uranium dioxide (UO₂), when undergoing fission, produce other elements, such as xenon. Xenon atoms tend to aggregate into bubbles in UO₂ and degrade the properties of the fuel as well as cause a physical swelling. We seek to understand the beginnings of xenon bubble formation in UO₂, using ab initio calculations.

Noble gas atoms in the interstitial sites of UO₂ induce strain, indicated by pink areas (left). The strain can be relieved by creating a cavity for a bubble to form (right). There will be a point at which the savings of relieving the strain energy of the dispersed noble gas atoms outweigh the cost of creating the bubble to contain those atoms. From my DFT+U calculations, the number of xenon atoms needed for the bubble to be energetically favored is one.

Biography

BS. Materials Science and Engineering, Purdue University, 2007

Publications

Google Scholar Profile

A. Thompson, C. Wolverton, First-principles study of noble gas impurities and defects in UO₂, Physical Review B 84 134111

B. Meredig, A. Thompson, H.A. Hansen, C. Wolverton, (2010) Method for locating low-energy solutions within DFT+U, Physical Review B 82 195128

and Engineering 17 015007

A. Thompson, A Strachan, (2010) Complex martensitic nanostructure in Zr nanowires: A molecular dynamics study, Physical Review B 81 085429

K. Lynch, A. Thompson, A. Strachan, (2009) Coarse grain modeling of spall failure in molecular crystals: role of intra-molecular degrees of freedom, Modeling Simulation in Materials Science