Ansari Narjes, Laio Alessandro, Hassanali Ali
The Abdus Salam International Centre for Theoretical Physics , Strada Costiera 11 , 34151 Trieste , Italy.
SISSA , Via Bonomea 265 , I-34136 Trieste , Italy.
J Phys Chem Lett. 2019 Sep 19;10(18):5585-5591. doi: 10.1021/acs.jpclett.9b02052. Epub 2019 Sep 6.
Some liquids are characterized by the presence of large voids with dendritic shapes and for this reason are dubbed transiently porous. By using a battery of data analysis tools, we demonstrate that liquid water and methane are both characterized by transient porosity. We show that the thermodynamics of porosity is distinct from that associated with cavitation á la classical nucleation theory. The shapes of dendritic voids in both liquids with very different chemistries resemble those of small polymers. We further show, using free energy calculations, that the cost of solvating small hydrophobic polymers in water is consistent with the work associated with creating dendritic voids. The entropic and enthalpic contributions associated with hosting these polymers can thus be rationalized by the thermodynamics of fluctuations in bulk water.
一些液体的特征是存在树枝状形状的大空隙，因此被称为瞬态多孔。通过使用一系列数据分析工具，我们证明液态水和甲烷都具有瞬态孔隙率。我们表明，孔隙率的热力学与经典成核理论中与空化相关的热力学不同。两种化学性质截然不同的液体中树枝状空隙的形状类似于小聚合物的形状。我们进一步通过自由能计算表明，在水中溶剂化小的疏水性聚合物的成本与产生树枝状空隙相关的功一致。因此，与容纳这些聚合物相关的熵和焓贡献可以通过大量水中波动的热力学来合理化。
