12:00 PM - 12:15 PM
[SIT20-04] Pressure-induced structural change in magnesium silicate melts
Keywords:magnesium silicate melts, liquid structure, phase diagram
Recently, a glass-glass transition of MgSiO3 was observed at 88 GPa and room temperature using X-ray diffraction measurement under static compression in a diamond anvil cell. It was suggested that this transition may be extended to a liquid-liquid transition of MgSiO3 melt at higher temperatures and pressures, which corresponds to the perovskite post-perovskite (Pv-PPv) transition of MgSiO3 crystal [3, 4].
Shock compression experiments for MgSiO3 [5, 6] and Mg2SiO4 [7, 8]melts have been also performed making it possible to explore the structure and properties of liquids directly.
In this presentation, we report the results of molecular dynamics simulation of magnesium silicate melts under high temperature and high pressure using various simulation schemes such as Empirical Potential Molecular Dynamics (EPMD) and First Principle Molecular Dynamics (FPMD) simulation as well as Large-scale First Principle Molecular Dynamics (L-FPMD) simulation for a consistent understanding.
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