2001 Volume 11 Issue 1 Pages 29-36
Applying pressure to hydrogen bonds significantly alters the bonding nature and induces various kinds of phase transitions. They are order-disorder transition, displacive transition, and bond symmetrization, and have intensively been investigated for ice as a prototype of a hydrogen-bonded system. The phase diagram of dense ice recently established at pressures up to 100 GPa and temperatures down to 0 K have revealed new aspects of physics and chemistry relating to the quantum behavior of protons such as tunneling. The phase relations and their physical implications are reviewed in this article.
