从水性酸溶液中的局部水化基因到宏观混合热力学:THz热量计的定量联系
Sampad Bag1, Simone Pezzotti1, Debasish Das Mahanta2
1Lehrstuhl für Physikalische Chemie II, Ruhr-Universität Bochum, Bochum 44780, Germany.
The journal of physical chemistry. B
|October 16, 2023
概括
我们通过太赫兹 (THz) 光谱和热量计探索了酸和水如何混合. 我们的发现将局部水化变化与宏观混合特性联系起来,揭示了对溶液行为的洞察力.
科学领域:
- 物理化学 物理化学
- 解决方案化学 解决方案化学
- 频谱学是一种光谱学.
背景情况:
- 了解液体混合物的热力学对于各种化学过程至关重要.
- 乙酸与水的混合物表现出复杂的行为,这是由于竞争的疏水性和疏水性相互作用.
研究的目的:
- 研究局部水化结构与水性酸溶液的宏观热力学特性之间的关系.
- 量化地将水化动机的变化与过度混合的和相关起来.
主要方法:
- 太赫兹 (THz) 光谱 (30-440 厘米-1) 用于探测分子间和 librational 模式.
- 采用了一种新的THz热量计方法,将光谱数据与热力学量联系起来.
- 在整个酸混合范围进行测量 (XAcAc = 0-1).
主要成果:
- 谱学可观测结果揭示了疏水性和亲水性水化基因的变化,其中酸度不同.
- 发现过多的混合度 (ΔH混合) 被疏水性和疏水性溶解影响.
- 过度的混合 (ΔS混合) 主要由疏水性空腔形成来控制.
结论:
- 乙酸水混合物由于内热溶解贡献,具有接近相位分离的特征.
- 在局部溶解平衡和宏观热力学特性之间建立了定量联系.
- 这项研究提供了对混合水溶液中水化动态的更深入的了解.
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