流体水中的两种局部结构共存的散射函数的直接证据
1Institute of Industrial Science , University of Tokyo , 4-6-1 Komaba , Meguro-ku, Tokyo 153-8505 , Japan.
Journal of the American Chemical Society
|January 22, 2020
概括
液态水表现出两种不同的局部结构,通过分析其结构因子来揭示. 这一发现澄清了关于水的长期争论
科学领域:
- 物理化学
- 材料科学
- 生物物理
背景情况:
- 液态水的独特特性对生命和工业至关重要.
- 液态水的基本结构仍然是一个争论的主题.
- 与其他液体相比,水的异常特性需要进行结构澄清.
研究的目的:
- 阐明液态水的基本结构组成部分.
- 解决长期存在的关于水分子排列的争议.
- 为实验确定水中的四面体结构提供一种方法.
主要方法:
- 使用计算机模拟三种突出的水模型.
- 分析最近的散射实验数据.
- 解结构因子的第一个衍射峰值.
主要成果:
- 在结构因子的第一个衍射峰值内确定了两个重叠的峰值.
- 与四面体水结构和密度波相关的异常峰值.
- 与非四面体局部结构相关的普通峰.
结论:
- 液态水中存在着两个不同的局部结构.
- 这些发现为长期存在的水结构辩论提供了关键的见解.
- 现在可以直接对四面体水结构进行实验量化.
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