Water molecules interact strongly “using” both the long range dipole-dipole and short-range “hydrogen bonds” to form sophisticated networks. As described in our previous post, water molecules align along a hydrophobic surface and form an strongly-interacting 2d system of molecular dipoles. Normally there is no true long range order at zero temperature in 2d, though there may still be a BKT-type order-disorder transition associated with dissociation of topological defects associated with the order parameter.
To clarify the nature of the water molecules configurations on a hydrophobic surface we chose the following simple field-theoretic model Free Energy functional of a water layer:
where
The phase transition in the model without Coulomb interaction () is described by the standard BKT theory. The power-law correlations of the polarization (quasi-long range order) change into exponentially decaying correlations at a finite temperature due to dissociation of the virtual vortex-antivortex pairs. Below we post an example (numerical) solution representing a pair of the hydrogen bonds network defects in a water-like liquid without long range interactions:

The red arrows represent the water molecules orientations (vector
Related posts:
- Molecular polarization on a polar liquid interface: the structure of a water surface
- Water polarization and density profiles at a gas-liquid interface
- Three great ways to calculate Born radii beyond the Coulomb Field Approximation
- How to use Born surface charges to calculate solvation energy?
- Non-polar contribution to solvation energy from Born models:
Pingback: Tweets that mention Quantum Pharmaceuticals » Blog Archive » Water molecules alignments on a hydrophobic surface – I -- Topsy.com