author={Li Zeng and Dimitar D. Sasselov},
  journal={The Astrophysical Journal},
For most planets in the range of radii from 1 to 4 R ⊕, water is a major component of the interior composition. At high pressure H2O can be solid, but for larger planets, like Neptune, the temperature can be too high for this. Mass and age play a role in determining the transition between solid and fluid (and mixed) water-rich super-Earth. We use the latest high-pressure and ultra-high-pressure phase diagrams of H2O, and by comparing them with the interior adiabats of various planet models, the… 

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