一个第一阶段的液态-液态相转换在中.
1Department of Synchrotron Radiation Research, Japan Atomic Energy Research Institute, Sayo, Hyogo. katayama@spring8.or.jp
Nature
|January 26, 2000
概括
第一阶段的液态-液态相变很少见,但在中观察到. 压力诱导了分子和聚合物液体形式之间的快速,可逆的结构变化,表明了新的相位过渡.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 物理化学 物理化学
背景情况:
- 第一个阶段结构过渡在固体中很常见.
- 在纯物质中,第一阶段的液态-液态相转变是非常罕见的.
- 之前的研究表明,在超冷水和液态碳中存在这种过渡.
研究的目的:
- 调查中液态-液态相变的可能性.
- 在不同压力条件下观察液体的结构变化.
主要方法:
- 在现场使用X射线衍射来研究液体.
- 实验是在不同的压力条件下进行的,特别是1GPa以上.
主要成果:
- 在液体中观察到压力诱导的结构转变.
- 确定了两种不同的液体形式:一种低压分子形式 (P4) 和一种高压聚合物形式.
- 这些形式之间的转变是急剧的,快速的,可逆的,并且发生在狭窄的压力范围内 (<0.02 GPa).
- 在过渡期间,两种液态形式的共存被注意到.
结论:
- 在液体中观察到的现象强烈地表明了第一阶段的液体-液体相转换.
- 这一发现为在极端条件下液态物质的行为提供了新的见解.
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