Ag55和Cu55集群之间的聚合动力学以及从原子模拟中冷却聚合集群的热力学
Jinhan Liu1,2, Lin Zhang1,2
1Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), Northeastern University, Shenyang 110819, China.
The journal of physical chemistry. A
|August 9, 2023
概括
分子动力学模拟揭示了初始集群结构如何影响铜 (Cu) 和银 (Ag) 集群的凝聚. 冷却导致不同的包装结构,影响热力学特性.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学计算化学
- 纳米技术 纳米技术
背景情况:
- 了解纳米级集群行为对于设计新材料至关重要.
- 双金属集群的凝聚和结构演变是复杂的现象.
研究的目的:
- 为了研究Cu55-Ag55集群凝聚的分子动力学.
- 分析凝聚集群在冷却过程中的结构变化.
- 确定初始集群结构 (液体,FCC,Ih) 对凝聚结果的影响.
主要方法:
- 使用了分子动力学模拟.
- 模拟追踪了集群相互作用,凝聚和冷却过程.
- 用洛德-纳达伊值来评估原子负载状态.
主要成果:
- 最初的集群结构显著影响凝聚阶段和最终结构.
- 与FCC相比,具有Ih结构的Cu集群在形成之前表现出更大的稳定性.
- 在冷却过程中,聚焦集群形成各种包装结构 (Ih,核心/外).
- 热力学行为与包装结构的顺序程度相关.
结论:
- 金属集群的初始结构配置决定了它们的凝聚路径和由此产生的形态.
- 冷却动力学驱动双金属集群中有序和转移稳定的结构的形成.
- 这项研究提供了纳米尺度结构转换的热力学控制的见解.
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