First-principles simulations within the local density and pseudopotential approximations were performed in order to investigate the effects of pressure upon the energetics and atomic and electronic structural behavior of vacancy defects in MgSiO3 perovskite. The simulations used a super-cell containing 160 atoms whose positions were fully optimized for each defective system. The Schottky formation energy was shown to increase by a factor of 2.5 over the pressure range studied (0 to 150GPa). The calculated 3-dimensional datasets for atomic configuration and electron charge density were studied in detail. It was shown that these point defects introduced substantial distortions into the surrounding atomic and electronic structures, and that these distortions remained nearly unchanged by pressure.

Computer Simulation and Visualization of Vacancy Defects in MgSiO3 Perovskite. B.B.Karki, G.Khanduja: Modelling and Simulation in Materials Science and Engineering, 2006, 14[6], 1041-52