Ab initio simulation of hydrogen bonding in ices under ultra-high pressure.

In this article, as continuation of the previous publication (P. Zhang, L. Tian, Z. P. Zhang, G. Shao, and J. C. Li, J. Chem. Phys. 137, 044504 (2012)), we report a series of computational simulation results for ices using ab initio DFT methods. The results not only reproduced the main feature of inelastic neutron scattering spectra for ice Ih, but also other phases of ice such as VII and VIII. Furthermore, pressure dependent simulations for ice I and VIII have led us to obtain the spectra for the symmetrical structure of ice X. The transition from normal ice to the symmetrical form shows an extraordinary behaviour of H-bonding in term of vibrations associated with inter- and intra-molecular bonds, revealing a range of phenomena which was not seen before.