在DMF的外部干扰下,探索水和重水的键结构的动态变化
Xiaokai Liu1, Suhan Wang1, Xueliang Xu1
1Key Laboratory of Physics and Technology for Advanced Batteries, College of Physics, Jilin University, Changchun 130012, China.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy
|October 18, 2023
概括
在水中的N,N-二甲基形式胺 (DMF) 增强了键,而不是在重水中. 在较高度下,DMF与水/重水形成集群,在压力下改变它们的结构.
科学领域:
- 物理化学 物理化学
- 频谱学是一种光谱学.
- 材料科学 材料科学 材料科学
背景情况:
- 了解溶液中的键网络对于化学和生物过程至关重要.
- N,N-二甲基形式胺 (DMF) 是一种常见的极性近极溶剂,与水有独特的相互作用.
研究的目的:
- 为了研究N,N-二甲基形式胺 (DMF) -水/重水二元溶液的键结构.
- 阐明DMF在改变水和重水的键网络中的作用.
主要方法:
- 拉曼光谱法用于分析DMF-水/重水二元溶液.
- 在DMF与水/重水的各种体积比率下进行了测量.
主要成果:
- DMF (低于40%) 通过替换四面体结构中的水分子来加强水的键,这种效应在重水中没有见过.
- DMF (60%以下) 与重水相互作用,影响OD共价键的对称性.
- 在较高的DMF度下 (40%/60%以上),四面体结构被DMF-水/重水集群 (例如,DMF·3H2O) 取代.
- 来自脉冲激光的动态高压将键结构过渡点转移到15%的DMF.
结论:
- DMF显著影响水溶液的键结构,对水和重水有明显的影响.
- 在较高的DMF度下观察到特定的DMF-水/重水集群的形成.
- 脉冲激光诱导的高压可以改变这些溶液中键结构的过渡点.
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