pressure-driven self-organization of water molecules in ferrierite

The water molecules, initially disordered, spontaneously organize in square tetrameric units. The water squares, once formed, remain stable - even upon returning to atmospheric pressure.

Atom colors. Si-FER framework (in sticks) - Si: yellow; O: red. Guest molecules (in van-der-Waals representation) - Ethanol (EtOH): C: cyan; O: red; H: white. Water: O: blue; H: white.

The movie (in mp4 format) was obtained the equiibration phases of a first-principles molecular dynamics simulation of the composite. In this trajectory, the cell parameters were those experimentally determined at pressure = 0.84 GPa with the diamond anvil cell and a 1:3 ethanol-water mixture as pressure transmitting medium.

Simulation temperature: room conditions (298 K)

This research is described in the paper:

"Irreversible conversion of a water-ethanol solution in an organized two-dimensional network of alternating supramolecular units in a hydrophobic zeolite under pressure." Angewandte Chemie; DOI: 10.1002/anie.201610949 and 10.1002/ange.201610949

Green open access version:

http://bit.ly/2De8HQq

Popular summary of the research:

https://goo.gl/HxR831

Blog post explaining this paper:

https://yourmoleculardreams.blog/2017/01/18/under-pressure-from-chaos-to-order/

Movie of the equilibrium behaviour of the composite:

https://figshare.com/articles/Ethanol_dimers_and_water_tetramers_in_zeolite_ferrierite_at_high_pressure/4530449

Links to original research article:

http://dx.doi.org/10.1002/anie.201610949

http://dx.doi.org/10.1002/ange.201610949

Links to the cover picture:

http://dx.doi.org/10.1002/anie.201700219

http://dx.doi.org/10.1002/ange.201700219

News article in MRS Bulletin covering this work:

https://www.cambridge.org/core/journals/mrs-bulletin/article/div-classtitlehigh-pressure-and-small-spaces-create-order-from-disorderdiv/7DDFCC976A75CAC0684F7C8DD6723596/core-reader