Modeling Atomic-Scale Processes in Crystalline Materials

Project Description The Materials Modeling Group at Northern Kentucky University uses computer simulation methods to study point defects and diffusion in crystalline materials. The group has studied both ceramic and metallic materials, but recent efforts have focused on intermetallic compounds with funding support from the National Science Foundation (RUI: Search for Verifiable Complex Diffusion Mechanisms, grant number DMR 15-08189). Intermetallic compounds are used throughout industry with applications in fields ranging from medicine to defense. A key to developing new, improved intermetallic materials is developing a better fundamental understanding of how atomic-scale defects affect materials properties and how atoms move in these compounds. Research activities in this group are divided into two projects: use of computer simulations (1) to predict defect and diffusion properties in intermetallic and other crystalline materials and (2) to help interpret data obtained from a class of experimental techniques called hyperfine methods.


Energy minimization and molecular dynamics techniques are used to calculate defect formation, association, and migration energies. Results of these simulations are combined with thermodynamic models and theories of atomic diffusion to predict diffusion properties and defect-induced changes in materials properties. Two models for interactions are used, depending on the length- and time-scales of the simulation: density functional theory for the electronic scale and empirical potentials (e.g., the second nearest neighbor modified embedded atom method) for the atomic scale. Commercially available software is used for these simulations.