Connecting water correlations, fluctuations, and wetting phenomena at hydrophobic and hydrophilic surfaces

Rahul Godawat; Sumanth N. Jamadagni; Vasudevan Venkateshwaran; Shekhar Garde

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arXiv · 1409.2570

Connecting water correlations, fluctuations, and wetting phenomena at hydrophobic and hydrophilic surfaces

Rahul Godawat·Sumanth N. Jamadagni·Vasudevan Venkateshwaran·Shekhar Garde

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Abstract

We use molecular simulations to demonstrate the connection between transverse water-water correlations and wetting phenomena for a range of hydrophobic to hydrophilic solid surfaces.Near superhydrophobic surfaces, the correlations are long ranged, system spanning, and are well described by the capillary wave theory. With increasing surface-water attractions, the correlations are quenched. At the critical attraction at which long range correlations disappear, the density profile normal to the surface changes from sigmoidal to layered, and the fluid begins to wet the surface. This behavior is displayed by both water and a Lennard-Jones fluid, highlighting the universality of the underlying physics.

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Rahul Godawat, Sumanth N. Jamadagni, Vasudevan Venkateshwaran, Shekhar Garde. 2014-09-09. Connecting water correlations, fluctuations, and wetting phenomena at hydrophobic and hydrophilic surfaces. https://arxiv.org/abs/1409.2570

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