了解二元玻璃形成液体中化温度的玻璃动态
Yunhuan Nie1,2, Lijin Wang3, Pengfei Guan1
1Beijing Computational Science Research Center, Beijing 100193, People's Republic of China. pguan@csrc.ac.cn.
Soft matter
|January 25, 2024
概括
在软核二进制液体中,粒子动力学与压力有着惊人的反向,挑战了小粒子总是移动得更快的观念. 这种动态逆转与有效的化温度和压力依赖性行为有关.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 统计力学 统计力学
背景情况:
- 通常预计在混合物中,小颗粒的移动速度比较快.
- 玻璃成型液体表现出复杂的动态,包括动态异质性,这对于理解其特性至关重要.
研究的目的:
- 为了研究不同压力下的二元玻璃形成液体中大颗粒和小颗粒之间的反直觉动态反转.
- 探索粒子相互作用 (软核与硬核) 和有效融温度在这种动态反转中的作用.
主要方法:
- 用分子动力学模拟来建模具有软核和硬核相互作用的二元玻璃形成液体.
- 分析重点是粒子动力学,结构松,动态异质性,以及作为压力函数的有效融温度.
主要成果:
- 在软核系统中观察到一个动态反转:在更高的压力下,小粒子变得比大粒子慢.
- 硬核系统中没有这种反转,这凸显了交互类型的重要性.
- 粒子的有效化温度与它们的放松动态相关,较高的化温度表明放松速度较慢.
结论:
- 软核系统的动态逆转归因于有效融温度的非单调压力依赖.
- 操纵粒子软度可以消除动态反转,证明对粒子动态的控制.
- 这项研究揭示了非平衡玻璃形成者和平衡晶体形成者之间的联系,特别是在化行为和动态方面.
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