Structure of supercooled and glassy water under pressure.

We use molecular-dynamics simulations to study the effect of temperature and pressure on the local structure of liquid water in parallel with neutron-scattering experiments. We find, in agreement with experimental results, that the simulated liquid structure at high pressure is nearly independent of temperature, and remarkably similar to the known structure of the high-density amorphous ice. Further, at low pressure, the liquid structure appears to approach the experimentally measured structure of low-density amorphous ice as temperature decreases. These results are consistent with the postulated continuity between the liquid and glassy phases of H2O.