Ground-state structures of ice at high pressures from ab initio random structure searching

  title={Ground-state structures of ice at high pressures from ab initio random structure searching},
  author={Jeffrey M. McMahon},
  journal={Physical Review B},
Ab initio random structure searching based on density functional theory is used to determine the ground-state structures of ice at high pressures. Including estimates of lattice zero-point energies, ice is predicted to adopt at least three crystal phases beyond $Pbcm$. The underlying sublattice of O atoms remains similar among them, and the transitions can be characterized by reorganizations of the hydrogen bonds. The symmetric hydrogen bonds of ice X and $Pbcm$ are initially lost as ice… 

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