在玻璃形成液体中高温液体-液体相变 Pd43Ni20Cu27P10
Huanyi Zhou1, Pengfei Yu2, Xiaoyu Miao1
1School of Materials Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China.
Materials (Basel, Switzerland)
|June 28, 2023
概括
这项研究揭示了液体中不寻常的热现象背后的结构机制. 研究人员在特定的玻璃形成液体中观察到异常的内热液体-液体相过渡 (LLPT),进步LLPT的理解.
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:
- 液态-液态相转换 (LLPT) 涉及具有不同的结构但相同组成的液态之间的变化.
- 在液体中,LLPT提供了对结构属性关系和热力学/动力学异常的洞察.
- 了解LLPT的结构驱动因素对于材料设计和基础科学至关重要.
研究的目的:
- 为了验证和研究Pd43Ni20Cu27P10玻璃形成液体中异常的内热液体-液体相变 (LLPT).
- 为了阐明原子层次的结构机制,负责在LLPT期间观察到的热捕获现象.
- 为了加深对LLPT及其相关热力学异常的基本理解.
主要方法:
- 使用闪光差分扫描热量计 (FDSC) 来实验检测和描述内热LLPT.
- 最初的分子动力学 (AIMD) 模拟被用来探测分子层面的原子结构和动力学.
- 分析的重点是局部原子结构的变化,特别是围绕Cu-P键的变化,以及特定的集群群体 (<0 2 8 0>和 <1 2 5 3>).
主要成果:
- 在Pd43Ni20Cu27P10玻璃形成液体中的异常内热LLPT被实验证实.
- AIMD模拟显示,Cu-P键周围的局部原子结构的变化导致特定集群群体的变化.
- 这些结构修改被确定为在相位过渡期间异常的热捕获效应的直接原因.
结论:
- 该研究成功地确定了特定的结构机制,涉及Cu-P键环境和集群重组,诱导内热LLPT.
- 这些发现提供了对液体中热捕获现象的基本理解,将结构变化与热力学行为联系起来.
- 这项研究有助于更好地理解液体-液体相位过渡及其基础的原子级过程.
关键词:
Pd-Ni-Cu-P-Pd-Ni-Cu-Pd-Ni-Cu-Pd-Ni-Cu-Pd-Ni-Cu-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Pd-Ni-Cu-Pd-Pd-Ni-Ni-Cu-Pd-Pd-Ni-Ni-Ni-Ni-Ni-Cu-Pd-Pd-Ni-Ni-Ni-Ni-Ni-Ni-Ni-Ni-Ni-Ni一开始的分子动力学.这是一种内热式内热式.闪光差分扫描热量计.流体流体阶段过渡的过渡过程.
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