Ice XV: A New Thermodynamically Stable Phase of Ice
Abstract
A new phase of ice, named ice XV, has been identified and its structure determined by neutron diffraction. Ice XV is the hydrogen-ordered counterpart of ice VI and is thermodynamically stable at temperatures below ∼130K in the 0.8 to 1.5 GPa pressure range. The regions of stability in the medium pressure range of the phase diagram have thus been finally mapped, with only hydrogen-ordered phases stable at 0 K. The ordered ice XV structure is antiferroelectric (P1¯), in clear disagreement with recent theoretical calculations predicting ferroelectric ordering (Cc).
- Publication:
-
Physical Review Letters
- Pub Date:
- September 2009
- DOI:
- 10.1103/PhysRevLett.103.105701
- arXiv:
- arXiv:0906.2489
- Bibcode:
- 2009PhRvL.103j5701S
- Keywords:
-
- 64.60.Cn;
- 61.05.fm;
- 61.50.Ks;
- 64.70.kt;
- Order-disorder transformations;
- statistical mechanics of model systems;
- Neutron diffraction;
- Crystallographic aspects of phase transformations;
- pressure effects;
- Molecular crystals;
- Condensed Matter - Materials Science;
- Condensed Matter - Other Condensed Matter
- E-Print:
- doi:10.1103/PhysRevLett.103.105701