高压下烯:一个分子晶体转化为和网络的故事,可能有中间金属相
Xiao-Dong Wen1, Roald Hoffmann, N W Ashcroft
1Baker Laboratory, Department of Chemistry and Chemical Biology, Clark Hall, Cornell University, Ithaca, New York 14853, USA.
Journal of the American Chemical Society
|April 29, 2011
概括
高压将转化为聚合物,但分子相持续转化稳定. 金属状态可能存在于180-200 GPa之间,聚合障碍影响过渡.
科学领域:
- 理论化学 理论化学
- 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
背景情况:
- 在不同压力下表现出多样化的分子相.
- 了解高压行为对于材料设计至关重要.
研究的目的:
- 研究的结构变化,高达300 GPa.
- 识别潜在的金属状态和聚合途径.
主要方法:
- 对的相稳定性的理论计算.
- 分子和聚合物相之间的度比较.
- 对分子重组的动力障碍的分析.
主要成果:
- 观察到已知的相位过渡低于20 GPa.
- 确定了一种50 GPa以上的稳定一维聚合物.
- 发现分子III相 (P2(1)/c) 转移稳定性高达200GPa.
- 预测了潜在的金属分子烯状态 (180-200 GPa).
- 预测了新的二元,表明了聚合过程的步骤.
结论:
- 在高压下转化为和聚合物.
- 存在转移稳定的分子相和潜在的金属状态.
- 动力障碍影响压力诱导的聚合.
相关概念视频
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