化物表面倾向的变化与滴滴大小和温度:平面接口的极限
Victor Kwan1, Styliani Consta1, Shahrazad M A Malek2
1Department of Chemistry, The University of Western Ontario, London, ON, Canada N6A 5B7.
The journal of physical chemistry. B
|December 21, 2023
概括
较大的水集群在表面显示的化物离子比较少. 这种离子分布与温度的变化会影响大气化学和核化过程.
科学领域:
- 物理化学 物理化学
- 化学物理 化学物理
- 计算化学的计算化学
背景情况:
- 之前的研究以计算方式分析了小水中的离子分布 (半径1.4纳米).
- 小集群中化物离子的表面丰富程度可能不反映它们在更大的系统中的行为.
研究的目的:
- 为了研究水性团中化物离子的大小依赖的表面丰度.
- 为了检查温度对水界面的化离子分布的影响.
主要方法:
- 具有不同大小 (等分半径高达≈2.45 nm) 的水性星团的计算模拟.
- 模拟水性平面接口与化盐在室内和高温下.
主要成果:
- 较大的星团 (≈2.45 nm半径) 在内部呈现出较高的化离子密度,而不是表面.
- 在水性平面接口上观察到类似的化物内部偏好.
- 高温降低了Cl−的表面倾向,而I−保留了一些表面亲和力.
结论:
- 混乱型化物离子的位置在更大的中和在更高的温度下向大体内部转移.
- 这种由温度引起的变化会影响光化学反应,核和盐结晶.
- 常见的力场参数化方法可能缺乏在不同系统中预测离子行为的可转移性.
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