Pressure-induced dissociation of water molecules in ice VII.

ABSTRACT: The neutron diffraction pattern of D2O ice was recently measured at pressures up to 52 GPa by Guthrie et al., who proposed an octahedral interstitial model for ice at pressures above 13 GPa to account for the deviation of the observed crystal structure from that of ice VII. In this article, the octahedral interstitial model was re-examined in terms of the interstitial occupancy and X-ray Raman spectroscopy (XRS) spectra. The interstitial occupancy calculated using first-principles molecular dynamics simulations was negligibly small compared to that of the interstitial model. The oxygen K-edge spectra calculated for the interstitial model exhibited two additional low-energy peaks originating from water molecules and hydroxides that are interacting with interstitial protons, respectively, wh

SUBMITTER: Iitaka T 

PROVIDER: S-EPMC4515761 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature