缓慢的溶解动力学超出了三脉冲光子回声峰值转移的介电松
JunWoo Kim1,2, Pyoungsik Shin1, Taiha Joo1
1Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang 37673, Republic of Korea.
The Journal of chemical physics
|August 8, 2023
概括
研究人员使用三脉冲光子回声峰值转移 (3PEPS) 光谱来研究液体动力学. 他们发现了缓慢的动态,可能是由于类似玻璃的集群,即使在点以下也持续存在.
科学领域:
- 物理化学 物理化学
- 化学物理 化学物理
- 材料科学 材料科学 材料科学
背景情况:
- 液态动力学和溶液合对于理解液相化学过程至关重要.
- 溶液的时间相关函数通常由于同质溶液中的溶剂运动而衰变.
研究的目的:
- 用先进的光谱学研究液体动力学和溶液合.
- 通过广泛的时间尺度 (从femtosecond到nanosecond) 和温度范围 (80-298K) 来解决动态.
主要方法:
- 使用基于衍射光学的三脉冲光子回声峰值转移 (3PEPS) 装置.
- 采用3PEPS,第三阶非线性光谱技术,测量溶液时间相关函数.
- 多种实验条件,包括温度和探测器溶解物分子.
主要成果:
- 观察到的动态比n-酒精介电松慢,即使在室温下也是如此.
- 确定了一个持久的~0.5 ns时间常数和一个纳秒时间尺度的静态偏移.
- 动力学在研究液体的点以下持续存在.
结论:
- 建议在液体中形成的局部形成的,类似玻璃的集群是观察到的缓慢动态的原因.
- 结果为液态动力学,液态玻璃转换和液态液态相转换提供了新的视角.
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