9526927 Bukowinski This project will develop a self consistent set of ab initio models for the response of deformable ions to crystal environments using density functional theory. The models will be used to examine the static and dynamic properties of transition zone and lmwer mantle minerals composed of SiO2, MgO, FeO, CaO and Al2O3, including perovskites, MgSiO3 Majorite, and other garnets and phases containing tetrahedral coordination polyhedra. Monte Carlo, molecular dynamics, simulated annealing techniques will be used to explore mineral structures at intermediate to very high pressures and temperatures, and to estimate thermal parameters needed to model mineral assemblages that may account for the observed seismic properties of the mantle. This will lead to a better understanding of possible sources of radial discontinuities deep in the lower mantle, and of thermal, structural and chemical effects on seismic velocities and the geochemical evolution of the earth.
