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Theoretical determination of the Raman spectra of MgSiO3 perovskite and post-perovskite at high pressure

Razvan Caracas·Ronald E. Cohen
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Abstract

We use the density functional perturbation theory to determine for the first time the pressure evolution of the Raman intensities for a mineral, the two high-pressure structures of MgSiO3 perovskite and post-perovskite. At high pressures, the Raman powder spectra reveals three main peaks for the perovskite structure and one main peak for the post-perovskite structure. Due to the large differences in the spectra of the two phases Raman spectroscopy can be used as a good experimental indication of the phase transition.

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Razvan Caracas, Ronald E. Cohen. 2006-03-08. Theoretical determination of the Raman spectra of MgSiO3 perovskite and post-perovskite at high pressure. https://doi.org/10.1029/2006gl025736

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