Ab initio infrared absorption study of the hydrogen-bond symmetrization in ice

We computed from first principles the infrared spectrum of ice at high pressure in the molecular phases VIII and VII and in the symmetric phase X by performing Car-Parrinello molecular dynamics simulations and evaluating the electronic polarization by means of the Berry phase formulation. The theoretical spectra are in good agreement with the experimental data and let us establish an unambiguous correspondence between the infrared spectrum and the underlying structure of the three different phases of ice. [S0031-9007(98)06844-6].