水中的离子 (H(aq) +) 的结构
Evgenii S Stoyanov1, Irina V Stoyanova, Christopher A Reed
1Department of Chemistry, University of California, Riverside, California 92521-0403, USA.
Journal of the American Chemical Society
|January 19, 2010
概括
水性离子,H ((aq) ((+),是一个独特的H ((13) O ((6) ((+) 实体,而不是Eigen或Zundel离子. 液态水在移动正电荷方面出色,挑战了当前化学教科书的描述.
科学领域:
- 物理化学 物理化学
- 水性化学 水性化学
- 频谱学是一种光谱学.
背景情况:
- 水中离子的结构,H ((aq) ((+),对于理解水化学至关重要.
- 现有的模型通常将其描述为Eigen (H(3) O(+)) 或Zundel (H(5) O(2) ((+)) 离子.
研究的目的:
- 为了阐明液态水中离子的精确结构.
- 为了研究水性环境中正电荷移位的程度.
主要方法:
- 红外 (IR) 光谱学被用来探测H的结构.
- 分析的重点是离子内部的中央氧-氧 (O...O) 分离.
主要成果:
- 在水中的离子被确定为一个独特的H{13) O{6} +) 实体.
- 观察到一个意想不到的长时间的中央O...O分离 (>2.43 Å).
- 与气体和固体相比,液态水在移动正电荷方面表现出独特的能力.
结论:
- 已建立的Eigen和Zundel离子模型不足以描述H ((aq) ((+).
- 这些发现需要对化学教科书中H(aq) ((+) 的呈现方式进行修订.
- 对于水性质子子运输机制来说,更好地了解正电荷移位是至关重要的.
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