充满的石英般的水冰
Timothy A Strobel1, Maddury Somayazulu1, Stanislav V Sinogeikin2
1Geophysical Laboratory, Carnegie Institution of Washington , Washington, D.C. 20015, United States.
Journal of the American Chemical Society
|August 20, 2016
概括
研究人员阐明了 (H2) +水 (H2O) 系统中的六角"C0"相结构. 这种类似石英的状结构,在岩状的道中含有大量的气,这与冰冷的行星有关.
科学领域:
- 高压物理与化学
- 材料科学
- 星球科学
背景情况:
- H2+H2O系统对于了解行星内部至关重要.
- 一个新的C0阶段最近被发现,但它的结构仍然未解决.
研究的目的:
- 要确定C0阶段的晶体结构.
- 了解这个阶段的储存机制.
- 评估它与冰冷的行星天体的相关性.
主要方法:
- 在现场拉曼光谱
- 单晶X射线衍射
- 粉末X射线衍射
主要成果:
- 在400MPa和280K时形成C0阶段,其名义成分为 (H2O) 2H2.
- 它具有形六角结构,具有相互透的螺旋链和无序的H2分子.
- 该结构具有能够容纳5.3%重量的类通道.
结论:
- C0阶段代表了一个独特的结晶格,具有储存的潜在应用.
- 它的结构特征和形成条件与冰冷行星的热力学环境有关.
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