The exclusion zone is a large stratum (typically on the order of a few microns to a millimeter) observed in pure liquid water, from which particles of other materials in suspension are repelled.
[5][6] The Exclusion zone has been observed using different techniques, e.g. birefringence, neutron radiography, nuclear magnetic resonance, and others,[4] and it has potentially high importance in biology, and in engineering applications such as filtration and microfluidics.
The first observations of a different behavior of water molecules, close to the walls of its container, date back to late 1960s and early 1970s, when Drost-Hansen, upon reviewing many experimental articles, came to the conclusion that interfacial water shows structural difference.
However, the hexagonal sheet hypothesis does not account for all aspects of the exclusion zone, and it is not supported by the majority of physicists.
Then, above a certain density threshold and below a specific critical temperature, those molecules go to another quantum state, with lower energy.