Liquids under Nanoscale Confinement

The few experimental results available appear to be in agreement with the above picture Pressure-induced formation of water wires in zeolite channels has been observed, and helical chains of an aqueous solution in CNTs were also observed by transmission electron microscopy (TEM). The transition from liquid to an amorphous bilayer above room temperature in 1 nm wide hydrophobic pores has also been simulated. On the other hand, MD results have been reported with water molecules forming an ordered layer in the region near the wall and showing no order along the axis of the nanotube, both in hydrophilic and in hydrophobic channels. The addition of CO2 was shown to induce layering along the walls of a 

A study of the transport properties of water in smaller tubes with diameters ranging from 1.1 to 2.1 nm suggested strong anisotropy, with axial diffusivity and viscosity being much larger that those in the radial direction, leading water molecules to assume an ordered, helical structure inside a [10,10] nanotube.  

X-ray diffraction [XRD] studies showed that a substantial amount of water adsorbed in SWNTs bundles, with a liquid-solid transition at 235 K. Simulation of XRD patterns suggested that water adsorbed primarily inside the tubes rather than in the interstitial channels of the bundle. Comparison of the vibrational and rotational spectra 

Experiments on capillary hlling of molten metals in 0.6-1.2 nm channels in zeolites show a much smaller threshold closer to 1 nm. This value was obtained considering that interphase transition 

This value differed from the macroscopic surface tension for each metal, and the difference has been attributed to the effect of the presence of the interface transition layers  

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A. Checco, Liquid spreading under nanoscale confinement, Phys. Rev. Lett, 102,106103 (2009]. 

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