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arXiv · 0906.2489

Ice XV: a new thermodynamically stable phase of ice

Christoph G. Salzmann·Paolo G. Radaelli·Erwin Mayer·John L. Finney
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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 ~130 K 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, in clear disagreement with recent theoretical calculations predicting ferroelectric ordering.

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Christoph G. Salzmann, Paolo G. Radaelli, Erwin Mayer, John L. Finney. 2009-06-14. Ice XV: a new thermodynamically stable phase of ice. https://doi.org/10.1103/physrevlett.103.105701

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