The mechanisms for pressure-induced amorphization of ice I(h)

J. S. Tse, D. D. Klug, C. A. Tulk, I. Swainson, E. C. Svensson, C. K. Loong, V. Shpakov, V. R. Belosludov, R. V. Belosludov, Y. Kawazoe

研究成果: Article査読

150 被引用数 (Scopus)

抄録

There has been considerable interest in the structure of liquid water at-low temperatures and high pressure following the discovery of the high- density amorphous (HDA) phase of ice I(h) (ref. 1). HDA ice forms at a pressure close to the extrapolated melting curve of ice, leading to the suggestion that it may have structure similar to that of dense water. On annealing, HDA ice transforms into a low-density amorphous (LDA) phase with a distinct phase boundary. Extrapolation of thermodynamic data along the HDA- LDA coexistence line into the liquid region has led to the hypothesis that there might exist a second critical point for water and the speculation that liquid water is mixture of two distinct structures with different densities. Here we critically examine this hypothesis. We use quasi-harmonic lattice- dynamics calculations to show that the amorphization mechanism in ice I(h) changes from thermodynamic melting for T > 162 K to mechanical melting at lower temperatures. The vibrational spectra of ice I(h), LDA ice and quenched water also indicate a structure for LDA ice that differs from that of the liquid. These results call into question the validity of there being a thermodynamic connection between the amorphous and liquid phases of water.

本文言語English
ページ(範囲)647-649
ページ数3
ジャーナルNature
400
6745
DOI
出版ステータスPublished - 1999 8 12

ASJC Scopus subject areas

  • General

フィンガープリント 「The mechanisms for pressure-induced amorphization of ice I(h)」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

引用スタイル