使用超高速红外光谱研究高度缩的液溶液的水力学和结构
Sean A Roget1, Kimberly A Carter-Fenk1, Michael D Fayer1
1Department of Chemistry, Stanford University, Stanford, California 94305, United States.
Journal of the American Chemical Society
|February 28, 2022
概括
在缩的盐溶液中,水比散装水形成更强的键. 这是由于新形成的水离子网络,
科学领域:
- 物理化学
- 化学物理
- 光谱学
背景情况:
- 高度的盐溶液会破坏水中的键 (H键) 网络.
- 离子迫使水以水-离子和离子-离子相互作用为基础进行重组.
研究的目的:
- 在缩化物溶液中研究水-水H键和方向动力学.
- 使用光谱学了解离子介质的结构演变.
主要方法:
- 稀释HOD的OD段的超快极化选择性探测 (PSPP) 光谱.
- 2D红外 (IR) 光谱检测光谱扩散.
主要成果:
- 在缩的LiCl溶液中,水与水的H键比在散装水中更强.
- 盐度的增加导致水分子的角限制和动态减缓.
- 与散装水相比,缩盐溶液中的光谱扩散动态显著减缓.
结论:
- 在缩的盐溶液中形成水离子网络,加强水-水 H 键并限制水分子动态.
- 频谱扩散的最慢组成部分反映了水分子在这个水离子网络中的重新排列.
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