CHEM
In the literature: open
Magnitude of the electric field at water-hydrophobic interfaces
In plain words
Some explanations of fast droplet chemistry need very strong electric fields right at the water surface. Measuring how strong these fields really are would test those explanations.
Precise statement
Determine the mean electric field projected on a probe bond at the water-air and water-oil interfaces at 300 K, from vibrational Stark shifts of interface-specific probes and from ab initio molecular dynamics, and compare with bulk water. The answer is the field magnitude (reported values range up to about $3e4\,\mathrm{statvolt}/\mathrm{cm}$) with its spatial profile across the interface.
What would settle it
Surface-selective vibrational Stark spectroscopy calibrated against bulk and ab initio simulations with the same probe.