High temperature elastic anisotropy of the perovskite and post- perovskite polymorphs of Al2O3
نویسندگان
چکیده
[1] Finite temperature ab initio molecular dynamics calculations were performed to determine the high temperature elastic and seismic properties of the perovskite and post-perovskite phases of pure endmember Al2O3. The post-perovskite phase exhibits very large degrees of shear-wave splitting. The incorporation of a few mole percent of Al2O3 into MgSiO3 is predicted to have little effect on the perovskite to post-perovskite phase transition pressure and seismic properties of the postperovskite phase; although a small difference in shearwave splitting may be observable. Citation: Stackhouse, S., J. P. Brodholt, and G. D. Price (2005), High temperature elastic anisotropy of the perovskite and post-perovskite polymorphs of Al2O3, Geophys. Res. Lett., 32, L13305, doi:10.1029/2005GL023163.
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