Direct observation of symmetrization of hydrogen bond in δ-AlOOH under mantle conditions using neutron diffraction.

ABSTRACT: At ambient pressure, the hydrogen bond in materials such as ice, hydrates, and hydrous minerals that compose the Earth and icy planets generally takes an asymmetric O-H···O configuration. Pressure significantly affects this configuration, and it is predicted to become symmetric, such that the hydrogen is centered between the two oxygen atoms at high pressure. Changes of physical properties of minerals relevant to this symmetrization have been found; however, the atomic configuration around this symmetrization has remained elusive so far. Here we observed the pressure response of the hydrogen bonds in the aluminous hydrous minerals δ-AlOOH and δ-AlOOD by means of a neutron diffraction experiment. We find that the transition from P2₁nm to Pnnm at 9.0 GPa, accompanied by a change i

SUBMITTER: Sano-Furukawa A 

PROVIDER: S-EPMC6195538 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature