控制热力学液态-液态相变的脆弱性调节玻璃模型中的控制
Hai-Rong Qin1, Chun-Shing Lee2,3, Yong-Jun Lü1
1School of Physics, Beijing Institute of Technology, Beijing 100081, China.
Physical review. E
|December 20, 2023
概括
我们开发了一种模拟结构玻璃的新模型,可以调整液体脆弱性. 该模型揭示了与脆弱性相关的液态-液态相变和热容量异常.
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
- 计算化学的计算化学
背景情况:
- 结构玻璃和超冷液体具有复杂的行为.
- 了解动力脆弱性对于玻璃性能至关重要.
- 分子动力学模拟是研究这些系统的关键.
研究的目的:
- 为分子动力学模拟引入一种新的可辨别粒子玻璃模型.
- 为了研究动力脆弱性和热力学特性之间的关系.
- 探索超冷液体中的液体-液体相位过渡和潜在能量景观.
主要方法:
- 开发一个可调节的可辨别粒子玻璃模型.
- 超冷液体的分子动力学模拟.
- 动力脆弱性,热容量和潜在能源景观的分析.
- 用高斯激发模型来解释的应用.
主要成果:
- 该模型允许在广泛范围内灵敏地调整动力脆弱性.
- 在玻璃过渡温度以上观察到热力学液-液相过渡.
- 确定了恒定体积的最大热容量,根据脆弱性而有所不同.
- 均衡的潜在能量景观对具有不同脆弱性的液体具有特征.
结论:
- 拟议的模型有效地模拟了结构玻璃及其性能.
- 动力脆弱性显著影响液体-液体相变和热力学行为.
- 高斯激发模型为理解这些现象在配置空间中的框架提供了一个框架.
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