
Nanotubes change the shape of water - dnetesn
https://phys.org/news/2018-08-nanotubes.html
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stephengillie
> _Shahsavari and his colleagues built molecular models of carbon and boron
> nitride nanotubes with adjustable widths. They discovered boron nitride is
> best at constraining the shape of water when the nanotubes are 10.5
> angstroms wide.

...

Shahsavari's team modeled water molecules, which are about 3 angstroms wide,
inside carbon and boron nitride nanotubes of various chiralities (the angles
of their atomic lattices) and between 8 and 12 angstroms in diameter. They
discovered that nanotubes in the middle diameters had the most impact on the
balance between molecular interactions and van der Waals pressure that
prompted the transition from a square water tube to ice._

From the images, they have 4 chains of water molecules within each nanotube,
arranged hydrogen-to-oxygen, creating a rectangle from the 4 chains. The ideal
nanotube is 3.5x wider than a water molecule.

Do boron nitride nanotubes work better because the alternating atoms create a
slightly more polar nanotube molecule than an all-carbon nanotube?

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tejtm
sounds like ice nine

> Shahsavari referred to the contents as two-dimensional "ice," because the
> molecules freeze regardless of the temperature.

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stephengillie
Fortunately it doesn't propagate beyond the nanotube. That would have been
tragic instead of novel.

