Work Geochemistry Department - Sandia National Laboratories PO Box 5800, MS 0754 Albuquerque NM 87185-0754 United Stateswork
Jeffery A. Greathouse
Sandia National LaboratoriesGeochemistry Department
- Layered minerals
- Gas hydrates
- Nanoporous materials
- Radiation damage to nuclear waste form materials
The aim of this research is to determine the equilibrium structure and dynamics of water and ions adsorbed to charged clay minerals using classical simulations based on validated clay force fields. Density functional theory is used to determine the local structure and vibrational dynamics of layer and surface hydroxyl groups, which aids in force field development. Using classical molecular dynamics simulations, one can examine the motion of ions and molecules in clay pores on a nanosecond timescale.
Gas hydrates are receiving much attention as a potential energy source (methane), medium for energy storage (hydrogen, methane) and sequestration (carbon dioxide). Molecular dynamics simulations are used to study the thermal expansion and vibrational properties of natural gas hydrates.
The adsorptive ability of nanoporous materials is key to a number of applications, including gas separation, contaminant detection and removal, and catalysis. Grand canonical Monte Carlo simulations are used to model the adsorption properties of nanoporous materials such as zeolites and metal organic frameworks (MOFs). Additionally, molecular dynamics simulation are used to model particle transport with the pores. These simulations enable predictive screening of the thousands of known materials for specific adsorption or separation applications in both the gas phase and aqueous solution.
Radiation Damage to Nuclear Waste Form Materials
The effect of radiation damage on candidate nuclear waste form materials is of great interest in the design of nuclear waste disposal processes. Molecular dynamics simulation is used to study a material’s ability to resist radiation damage. In particular, the initial damage and self-healing of materials such as silica glass and ceramics have been simulated.
- Ph.D. in physical chemistry, University of California, Davis. Dissertation
- B.S. in chemistry and mathematics, Southwestern University