2011/06/10 by Jeffrey M. McMahon · 1 citation
Chemistry · Earth and Planetary Sciences · Mathematics · Physics and Astronomy · #Ab initio #Advanced Chemical Physics Studies #Atomic physics #Chemistry #Computational chemistry #Crystal structure #Crystallography #Density functional theory #Geological and Geochemical Analysis #Geometry #Ground state #High-pressure geophysics and materials #Homogeneous space #Hydrogen bond #Ice Ih #Lattice (music) #Materials science #Mathematics #Molecule #Physics #Quantum mechanics #astro-ph.EP #cond-mat.mtrl-sci #cond-mat.other #physics.comp-ph
paper · pdf · doi:10.1103/physrevb.84.220104
10 pages; 5 figures
arxiv created 2011/06/10 · openalex publication_date 2011/12/13 · arxiv updated 2013/05/29 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
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 transforms to structures with symmetries Pmc21 (800--950 GPa) and P21 (1.17 TPa), but they are eventually regained at 5.62 TPa in a layered structure C2/m. The P21\ensuremath→C2/m transformation also marks the insulator-to-metal transition in ice, which occurs at a significantly higher pressure than recently predicted.