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# Water at hydrophilic surfaces
Water at hydrophilic surfaces will adsorb onto the surface up to 2-3 atoms thick layers (roughly 1 nm in thickness). This adsorbate can exchange hydrogen ions with the bulk water (auto-ionize). The hydrogen ions released then spread out by diffusion, while the hydroxide ions remain stuck within the crystalline structure of the adsorbate. The diffusion of the H+ outwards generates an electric field from the negatively charged (hydroxide-rich) adsorbate and the positively charged (hydronium-rich) bulk water. This electric field polarizes the water within it and it tends to organize into what Gilbert Ling called "multilayer polarized water", hundreds of thousands of atomic layers of polarized water. This "non-solvent water" as Gilbert Ling called it will exclude (or, expel, eject) particles. It can be observed by diffraction photographs on flash-frozen water at hydrophilic surface (McGeoch, 2008).
It is well established that water at hydrophilic surfaces forms a 2-3 atomic layers thick adsorbed phase. That the adsorbate will exchange hydrogen ions with the bulk water (by auto-ionization) and these spread out by diffusion and build an electric field is known by the laws of physics (asymmetry in mobility of charge carriers is the physical basis of the transistor as well). That electric field will polarize liquid water is known by the laws of physics.
The ordered structure of this water does not dissolve hydrogen ions well, and beyond it the pH homogenizes out to a certain distance (often 1 cm in lab experiments, see Chai, 2009). Electrically, the adsorbate and bulk water behave as a negative and positive plate with a charge-free region between them, and any measurements with electrodes will show this - with the reference electrode at the "positive plate", there is a strong voltage of roughly 200 mV with probe electrode at the adsorbate which then falls off abruptly as the probe moves into the "non-solvent water" to then continue to fall linearly until the probe reaches the bulk water. The high electrical potential measured with the probe electrode at the adsorbate, is electro-chemical, from the reaction 4 OH- --> 2 H2O + O2 + 4 e- at the adsorbate and the reaction 4 H+ + 4 e- + O2 --> 2 H2O at the protonated bulk water. These reactions are the same as in an acid-base electro-chemical battery (Weng, 2019).
The physical separation of the OH- and H+, with the OH- stuck within the adsorbate, is increased with the "exclusion zone" (Gerald Pollack's term for the "non-solvent water") acting as an insuling layer for H+. The recombination tendency is low, if disassociation of H2O happens it will have low tendency to recombine.
The degree of ionization in the adsorbate can be derived from counting the hydrogen ions released. The pH in lab experiments is pH 5.5 for 1 cm out from the surface (Chai, 2009). It must be 1 cm in nanometer (10^7) more concentrated when it was in the adsorbate. The molarity is then 10^7*10^-5.5 which is roughly half of the molarity of liquid water. Gerald Pollack's "fourth phase" has 50% ionization, (H3O2-)n, which fits perfectly. Any sufficiently ionized adsorbed phase would tend to collapse into the "fourth phase" as the hydrogen ions between the layers fail to keep the layers separated (and the layers thus shift half an oxygen atom to the electrostatically favoured structure).
Any liquid that can adsorb to a surface and that can auto-ionize by exchanging an hydrogen ion and that can polarize in an electric field could be predicted to demonstrate this effect. It has been shown in experiments with ethanol (Chai, 2010), but the electrical potential was found to be identical to in water (whereas it could be assumed the ionization in the ethanol adsorbate would be lower), which suggests there might be water contamination and it is in fact the water adsorbate that provides the ions, i.e., an artefact.
# References
McGeoch, J. E., & McGeoch, M. W. (2008). Entrapment of water by subunit c of ATP synthase. Journal of the Royal Society, Interface, 5(20), 311 318. https://doi.org/10.1098/rsif.2007.1146
Chai, B., Yoo, H., & Pollack, G. H. (2009). Effect of radiant energy on near-surface water. The journal of physical chemistry. B, 113(42), 13953 13958. https://doi.org/10.1021/jp908163w
Weng, G.-M., Li, C.-Y. V., & Chan, K.-Y. (2019). An Acid Base Battery with Oxygen Electrodes: A Laboratory Demonstration of Electrochemical Power Sources. Journal of Chemical Education, 96(8), 1701 1706. https://doi.org/10.1021/acs.jchemed.8b00901
Chai, B., & Pollack, G. H. (2010). Solute-free interfacial zones in polar liquids. The journal of physical chemistry. B, 114(16), 5371 5375. https://doi.org/10.1021/jp100200y
# Why adsorbed water is ionized at 50% and in what Pollack calls "the fourth phase"
It is well established that water at hydrophilic surfaces forms a 2-3 atomic layers thick adsorbed phase. The evidence points to that this adsorbate is ionized up to 50%. The reason the ionization is exactly at 50% is simple. Initially, the adsorbate is very ice-like and the honeycomb layers are separated by hydrogen atoms. Within the adsorbate, auto-ionization still happens (bonds are not completely locked but form and break partly continuously, a partially solid and partially liquid phase) and in contrast to liquid water, the ions are more asymmetric in their mobility. The hydroxide ion is almost entirely immobalized, it is stuck or locked within the crystalline structure, whereas the hydrogen ion is free to move by jumping from oxygen to oxygen, and then continue to jump out into molecules in the liquid water. As the hydrogen ions are free to move by diffusion, they will spread out as far as they can (until the electric field that forms to the negative charge is strong enough to halt further separation). The effect here is analogous to what happens in semiconductor junctions, the charge carriers are asymmetric in their mobility, so they separate as the more mobile one moves away by diffusion. Due to the physical separation of the ions, the recombination rate is reduced, so the equilibrium moves towards a much higher degree of ionization than in liquid water. Now then, once the ionization and H+ lost to the bulk water reaches a certain threshold, the hydrogen ions separating the honecomb sheets will not be able to overcome the pressure from the surrounding bulk water, the layers will collapse onto one another and do so in the physically favourable way: shifted half an oxygen atom so that the oxygens of one layer face hydrogen of the other (thus electrostatically favourable).
The laws of physics mean that any water adsorbate that forms will be ionized. Even if just one layer thick adsorbate formed, it will interact with the bulk water and auto-ionize with it (transfer hydrogen ions to it). The hydrogen bonding to the surface also means each oxygen binds its hydrogens weaker, and the immobilization of the oxygen means the hydroxide ion is immobile. The diffusion of the hydrogen ions into the bulk water physically separate them from the hydroxide ions, thus recombination tendency is reduced and the auto-ionization equilibrium shifts towards a higher degree of ionization. If the ionization reaches a certain threshold, the ice-like phase (with layers separated by hydrogen atoms) is no longer favourable, and the adsorbate logically has to collapse into the "fourth phase" and 50% ionization. Alternatively, the adsorbate might form by nucleating each layer directly as "fourth phase", it depends on which has more attractive force between the adsorbate and nucleating water molecules.
# The "fourth phase" chemically reacting with surfaces
The "fourth phase" is seen in how metals rust when exposed to water (Chai, 2012). A metal like iron when submerged in water is hydrophilic, and water adsorbs to it to a 2-3 atom layer thick adsorbate where auto-ionization lets the more mobile hydrogen ion escape while the hydroxide ion is stuck, and the phase prefers to distribute itself so the hydrogen ions between the sheets are the ones lost, and the sheets are shifted half an oxygen relative to one another: Gerald Pollacks "fourth phase" of water, (H3O2-)n. Quantatively, this phase gives off hydrogen ions that will lower the pH up to 1 cm outwards to pH 5.5 (Chai, 2009). Iron will react with the hydrogen ions that are released from the adsorbate, and be oxidized, Fe --> Fe^2+ + 2e-, and the electrons combine with the hydrogen ions and O2 (this requires external O2) as 4 H+ + 4 e- + O2 --> 2 H2O. This consumes the hydrogen ions, and the electric field is between the iron and the hydrogen ions (i.e., inwards, thus opposite in direction to the electric field at surfaces that do not oxidize, where the field is instead between the low pH region and the adsorbate, which is outwards). Due to the H+ being consumed in the rusting process the bulk water beyond the adsosrbate (and "exclusion zone" above it) is also alkaline rather than acidic. The rust reaction is fastest on the parts of the metal surface that is not covered by adsorbate which is why rust process is "patchy" (Chai, 2012).
Conventional understanding of rust is the O2 directly oxidizes the metal, 2 Fe + O2 + 2 H2O --> 2 Fe^2+ + 4 OH-, and the rate limiting step is the diffusion of O2 in either scenario, so it is hard to use rust as proof of the "fourth phase".
In non-oxidizing surfaces like quartz, SiO2, the reactions with the fourth phase are harder to dismiss with other mechanisms. The silicon dioxide reacts with the hydroxide ions in and from the fourth phase as SiO2 + 2 OH- --> SiO3^2- + H2O. The SiO3^2 disolves into the bulk water, and there it is protonated in the low pH region and can separate into SiO2 and H2O again (and polymerise during this step when multiple H2SiO3 react). The acid-base separation at the adsorbate and bulk water interface provides the exact conditions needed to move silicon dioxide from the quartz and into the bulk water, where it clumps together. In the 1960s and 1970s, scientists experimenting with water in quartz containers found that the water acted in a very anomalous way, it was much thicked than normal water, denser (Fedyakin, 1962; Derjaguin, 1973). They believed they had found a form of water with distinct properties, "anomalous water" or "water 2" (later known as "polywater"). Eventually it was discovered this "polywater" was just contaminants dissolved out of the container used, and the interest died out. The contaminants in the early "anomalous water" experiments provide strong evidence that the 2-3 atomic layers thick adsorbed water is in Pollack's "fourth phase" - the adsorbate (or near surface) phase has to be very strongly ionized to form the quantities of contaminats observed, the quantities far exceed what dissolves passively.
# References
Chai, B., Mahtani, A. G., & Pollack, G. H. (2012). UNEXPECTED PRESENCE OF SOLUTE-FREE ZONES AT METAL-WATER INTERFACES. Contemporary Materials, 1(3). https://doi.org/10.7251/com1201001c
Chai, B., Yoo, H., & Pollack, G. H. (2009). Effect of Radiant Energy on Near-Surface Water. The Journal of Physical Chemistry B, 113(42), 13953 13958. https://doi.org/10.1021/jp908163w
Fedyakin, N. N. (1962). "Change in Water Structure on Condensation in Capillaries", Kolloidnyi Zhurnal, 24, pp. 497 501.
DERJAGUIN, B. V., & CHURAEV, N. V. (1973). Nature of Anomalous Water. Nature, 244(5416), 430 431. https://doi.org/10.1038/244430a0