水的类似冰的动力学
Kouki Oka1, Hiroshi Akiba2, Norimitsu Tohnai1
1Department of Applied Chemistry and Center for Future Innovation (CFi), Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
The journal of physical chemistry letters
|January 2, 2024
概括
疏水溶剂中的水集群表现出令人惊的缓慢动态,甚至在结温度以上也"像冰一样"移动. 这项研究使用中子散射揭示了它们独特的行为.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 化学物理 化学物理
背景情况:
- 了解水动力学在科学学科中至关重要.
- 在疏水溶剂中已经确定了水集群的转移稳定状态.
- 观察水群动态是具有挑战性的,因为它们的丰度很低.
研究的目的:
- 为了研究-d6.6中的水集群的扩散动态.
- 描述这些水群的缓慢动态.
- 为了比较水集群的动态与大量的水和冰.
主要方法:
- 准弹性中子散射 (QENS) 的测量.
- 在日本研究反应堆 (JRR-3) 使用了AGNES飞行时间谱仪.
- H核磁共振光谱被用于初步识别.
主要成果:
- 水集群原子扩散速度明显低于散装水.
- 扩散系数低于可观测极限 (10-10m2/s).
- 水集群的动态类似于冰的动态,即使在水结点 (273 K) 以上的温度下也是如此.
结论:
- 水集群具有独特的,缓慢的动态,与溶解水和散装水不同.
- 这些星团在环境和高温下表现出类似冰的移动性.
- 这些发现为在非极地环境中水的行为提供了新的见解.
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