Stability of the MgSiO3 analog NaMgF3 and its implication for mantle structure in super-Earths

  title={Stability of the MgSiO3 analog NaMgF3 and its implication for mantle structure in super-Earths},
  author={Brent Grocholski and Sang‐Heon Shim and Vitali B. Prakapenka},
  journal={Geophysical Research Letters},
[1] First-principles calculations on MgSiO3 suggested a breakdown into MgO + SiO2 at pressure above 1000 GPa with an extremely large negative Clapeyron slope, isolating the lowermost mantles of larger super-Earths (∼10M⊕) from convection. Similar calculations predicted the same type of breakdown in NaMgF3 to NaF + MgF2 at 40 GPa, allowing for experimental examination. We found that NaMgF3 is stable to at least 70 GPa and 2500 K. In our measurements on MgF2 (an SiO2 analog), we found a… 

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