通过介电光谱学,去极化动态光散射和分子动力学分子动力学计算机模拟对双极-双极交叉相关性的实验性检查
K Koperwas1, J Gapiński2, Z Wojnarowska1
1Institute of Physics, University of Silesia in Katowice, 75 Pułku Piechoty 1, 41-500 Chorzow, Poland.
Physical review. E
|April 18, 2024
概括
在研究超冷极玻璃形成器时,这项研究揭示了光散射数据与介电电容量保持一致. 这与其他玻璃形成器不同,突出了各种各样的方向关联影响.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 由于介电和光散射光谱的交叉和自我相关性,了解超冷极玻璃形成者是复杂的.
- 范德瓦尔斯液体1,2-二乙烯碳酸盐 (DVC) 作为极相对应的正极 (OTP),使得比较动态研究.
研究的目的:
- 通过介电光谱学,去极化动态光散射 (DDLS) 和风学来研究DVC的动态.
- 为了比较DVC的动态与其他玻璃形成剂,如tributil phosphate (TBP),并了解方向相关性的作用.
主要方法:
- 介电光谱检测分子放松.
- 消极动态光散射 (DDLS) 来研究方向动态.
- 风湿学来评估粘弹性特性.
- 模型极性分子的计算机模拟.
主要成果:
- 对于DVC的光散射数据与其在广泛的温度范围内的介电电容度有很好的相关性.
- 在DVC中观察到的相关性模式与TBP显著不同,尽管具有相似的介电特性 (β_{KWW}=0.75, Δɛ=20).
- 计算机模拟表明交叉术语对极性分子中DDLS测量的相关函数有显著的贡献.
结论:
- 导向相关性对介电和光散射光谱的影响在DVC和TBP之间不同.
- 与TBP相比,DDLS对DVC的实验显示了不同的动态反应,表明了不同的分子相关性效应.
- 交叉相关性在极性分子系统中DDLS探测的动态中起着显著的作用.
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