含有宇宙热和热带阳离子的化离子液体的低频谱
Maharoof Koyakkat1, Tateki Ishida2, Kyoko Fujita3
1Department of Chemistry, Chiba University, 1-33 Yayoi, Inage-ku, Chiba 263-8522, Japan.
The journal of physical chemistry. B
|April 19, 2024
概括
在水合离子液体中,水对分子间振动的影响不同. 热态[ch][dhp]的相互作用减弱,而热态[ch]Br的相互作用保持不变,影响它们的大量性质.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 频谱学是一种光谱学.
背景情况:
- 离子液体 (ILs) 是可调节的溶剂,具有多种应用.
- 了解水对IL结构和动态的影响对于它们在水溶液中的使用至关重要.
- 化IL表现出独特的分子间振动特性,取决于离子类型 (宇宙热带与热带).
研究的目的:
- 为了研究在化胆二酸盐 ([ch][dhp]) 和胆化 ([ch]Br) ILs中分子间振动的水度依赖性.
- 阐明宇宙热带 ([dhp]−) 和热带 (Br−) 离子在这些振动变化中介作用.
- 为了将观察到的光谱变化与散装性质和分子动力学相关联.
主要方法:
- 五秒拉曼诱导的克尔效应光谱 (fs-RIKES) 来探测分子间振动.
- 分子动力学 (MD) 模拟以产生振动密度状态 (VDOS).
- 对VDOS光谱的分解分析,以确定不同分子组件的贡献.
主要成果:
- 一个低频谱峰 (~50厘米-1) 红移在水化[ch][dhp],表明弱化的分子间相互作用,归因于离子和水.
- 没有观察到水合[ch]Br与增加水度的显著峰值转移.
- 180厘米-1的带,分配给水阻碍转换运动,显示了两个IL的不同度依赖.
- 低频带的峰值频率与[ch][dhp]的批量参数相关,但与[ch]Br.Br.不相关.
结论:
- 阳离子的性质 (宇宙热带与热带) 显著决定了水如何影响液化ILs中的分子间振动和体积特性.
- [ch][dhp]相互作用被水削弱,影响其体积特性,与[ch]Br.Br.不同.
- fs-RIKES和MD模拟为水合离子液体的动态提供了互补的见解.
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