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arXiv · 1509.06164

Lattice dynamics of MgSiO$_3$ perovskite (bridgmanite) studied by inelastic x-ray scattering and ab initio calculations

Björn Wehinger·Alexeï Bosak·Sabrina Nazzareni·Daniele Antonangeli·Alessandro Mirone·Samrath Lal Chaplot·Ranjan Mittal·Eiji Ohtani·Anton Shatskiy·Saxena Surendra·Subrata Ghose·Michael Krisch
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Abstract

We have determined the lattice dynamics of MgSiO$_3$ perovskite (bridgmanite) by a combination of single-crystal inelastic x-ray scattering and ab initio calculations. We observe a remarkable agreement between experiment and theory, and provide accurate results for phonon dispersion relations, phonon density of states and the full elasticity tensor. The present work constitutes an important milestone to extend this kind of combined studies to extreme conditions of pressure and temperature, directly relevant for the physics and the chemistry of Earth's lower mantle.

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Björn Wehinger, Alexeï Bosak, Sabrina Nazzareni, Daniele Antonangeli, Alessandro Mirone, Samrath Lal Chaplot, Ranjan Mittal, Eiji Ohtani, Anton Shatskiy, Saxena Surendra, Subrata Ghose, Michael Krisch. 2015-09-21. Lattice dynamics of MgSiO$_3$ perovskite (bridgmanite) studied by inelastic x-ray scattering and ab initio calculations. https://doi.org/10.1002/2016gl067970

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