Study of H2O Ice To Megabar Pressures by Brillouin Scattering (CAT#: STEM-ST-0156-YJL)

Introduction

The phase behavior and compressibility of H2O ice at high pressure and temperature conditions have long been important problems in chemistry, physics, geology, planetology, and biology, and recent research continues to reveal new findings. Because of its open, hydrogen-bonded structure, H2O shows many structural changes between different crystalline forms under pressure. Below 2 GPa and at low temperatures, 12 structural polymorphs and amorphous phases are documented including many metastable forms. Above 2 GPa, three solid phases have been characterized experimentally to date—a high temperature proton disordered paraelectric ice VII, a low temperature proton ordered antiferroelectric ice VIII, and a symmetric hydrogen-bonded ice X.