在纳米封闭碳化中液态-液态相变
Weikang Wu1, Leining Zhang1, Sida Liu1
1Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials, Ministry of Education, Shandong University , Jinan 250061, People's Republic of China.
Journal of the American Chemical Society
|February 10, 2016
概括
我们在纳米裂中发现了液体-液体相位过渡的理论证据. 这种转变涉及层次化,密度变化和由限制和压力驱动的微相分离.
科学领域:
- 材料科学
- 物理化学
- 计算物理
背景情况:
- 液态碳化 (SiC) 是一个技术上重要的材料.
- 对于纳米技术来说,了解局限系统中的相位过渡至关重要.
- 之前的研究已经探讨了SiC的特性,但纳米裂封闭下的LLPT仍未得到充分研究.
研究的目的:
- 在纳米裂封闭下调查液体碳化液体相变 (LLPT) 的理论证据.
- 描述与LLPT相关的结构和密度变化.
- 阐明封闭,压力和壁液相互作用在诱导LLPT中的作用.
主要方法:
- 在纳米裂内对液态碳化进行理论建模和模拟.
- 结构性质的分析,包括协调数 (三协调,四协调,五协调结构).
- 研究密度变化和微相分离现象.
主要成果:
- 在封闭的液态碳化中进行液态液态相变 (LLPT) 的理论证据.
- LLPT的特点是层次过渡,显著的密度变化和结构分布的改变 (四和五协调结构).
- 由于强大的壁-液体力量和不同的协调结构,和碳在墙壁附近形成不同的层.
结论:
- 纳米裂封闭和压力可以诱导液体碳化的液态相变.
- 该LLPT涉及复杂的结构重组和微相分离,导致不同的富和富碳层.
- 限制和压力之间的相互作用决定了LLPT的主要驱动力,限制在高压下占主导地位,压力在低压下占主导地位.
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