核量子效应和Grotthuss机制决定了液态水的pH值
Saswata Dasgupta1, Giuseppe Cassone2, Francesco Paesani1,3,4,5
1Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, United States.
The journal of physical chemistry letters
|March 17, 2025
概括
这项研究使用先进的计算方法揭示了水自电离的分子机制. 它准确计算了自离子化常数 (pKw),并突出了格罗图斯机制.
科学领域:
- 物理化学 物理化学
- 计算化学的计算化学
- 化学物理 化学物理
背景情况:
- 水的自离子化成 (H3O+) 和氧化物 (OH-) 离子控制水溶液的特性.
- 了解这个过程对于化学和生化反应至关重要.
研究的目的:
- 确定水自电离的分子机制.
- 准确计算液态水的自离子化常数 (pKw).
主要方法:
- 深度神经网络潜力在密度纠正密度函数理论数据上训练.
- 增强的样本采集技术用于自由能源的景观勘探.
- 包括核量子效应在内.
主要成果:
- 精确估计液态水的自离子化常数 (pKw = 13.71 ± 0.16).
- 详细的分子层次图片的自离子化过程.
- 强调自电离的量子力学性质.
结论:
- 格罗图斯机制在稳定离子对方面发挥着关键作用.
- 这种机制显著影响水中的酸平衡.
相关概念视频
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Base ionization of a species occurs when it accepts protons from water molecules. In the example below, pyridine molecules, C5NH5, undergo base ionization when dissolved in water, yielding hydroxide and pyridinium ions:
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