在亚利法醇中软封闭水:MIR/NIR光谱和DFT研究
Mirosław Antoni Czarnecki1, Justyna Warchoł1, Kazimierz Orzechowski1
1Faculty of Chemistry, University of Wrocław, F. Joliot-Curie 14, 50-383 Wrocław, Poland.
概括
酸醇中的水溶性取决于溶剂结构,影响水.
科学领域:
- 物理化学 物理化学
- 频谱学是一种光谱学.
- 计算化学的计算化学
背景情况:
- 了解水在封闭环境中的行为对于各种化学和生物过程至关重要.
- 阿利法性酒精提供了一个模型系统,用于研究软封闭对水的影响,因为它们的结构各不相同.
研究的目的:
- 为了研究水的状态,限制在八种不同的亚利法醇.
- 为了将水溶性与溶剂分子结构和光谱特性相关联.
- 阐明水分子与酒精基 (OH) 基之间的相互作用.
主要方法:
- 卡尔·菲舍尔定位法用于确定和酒精溶液中的水含量.
- 减弱总反射-红外 (ATR-IR) 和近红外 (NIR) 光谱法用于监测水添加和温度效应.
- 密度函数理论 (DFT) 计算用于酒精水复合物的结构和能量分析.
主要成果:
- 在1-酒精中的水溶性随着链条长度的增加而下降,对更长的链条的影响较小.
- 由于OH组屏蔽,当从初级酒精转移到二级酒精时,溶解率的降低更为显著.
- 水在循环酒精中比线性酒精更容易溶解,这归因于OH组更好的可访问性.
结论:
- 亚利法醇中的水的状态与其溶解度直接相关,这是由溶剂结构决定的.
- 水分子没有被观察到作为自由实体;它们通过与酒精OH组的键相互作用.
- 在含有大量异质部分的酒精中,水分子主要位于OH组附近.
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