In General
* Properties: Its relatively high conductivity is due to the Grotthuss mechanism, in which positively charged hydrogen ions (protons) move rapidly from one water molecule to the next.
@ General references: Eisenberg & Kauzmann 69; Caro 93; Denny 93 [and air]; Ball 99 [r pw(00)feb]; issue JSP(11).
@ Cold, non-crystalline states: Smith et al PRL(97) + pn(97)jul [amorphous solid water]; Debenedetti & Stanley PT(03)jun.
@ Properties: Pellicer et al AJP(02)jul [surface tension]; news ns(11)oct [quantum origin of water's properties]; news mainz(13)jul [Grotthuss mechanism]; Arbe et al PRL(16) + Teixeira Phy(16) [dielectric constant].
@ Related topics: Jiang & Schrader PRL(98) + pn(98)nov [positronic water]; Bergeron & Quéré pw(01)may [bouncing droplets]; Waltham phy/02 [heavy water in Canada]; Mattsson & Desjarlais PRL(06) + pn(06)aug [conducting at T = 4000 K, p = 100 GPa]; Hock et al PRL(09) + Fernández-Serra Phy(09) [small clusters and size-dependent phase diagrams]; Feibelman PT(10)feb [wetting of solids]; Nagata et al PRL(12) [nuclear quantum effects and the structure of water-vapor interfaces]; Vollmer & Möllmann TPT(13)oct [size of raindrops]; Elton & Spencer a2010-ch [pathological science].
> Online resources: see Wikipedia page.

Phase Transitions > s.a. phase transitions.
* Critical points: Water has a well-known critical point at about 374°C and 218 atm, above which liquid water and water vapor become indistinguishable, a triple point at 273.1600 K, and a critical point hidden deep in the supercooled regime; At temperatures below that point, there exist two distinct liquid phases of different densities.
* Mpemba effect: The observation that initially hot water freezes faster than initially cold water; The claim has been very controversial but appears to be real; Support comes in part from controlled experiments with tiny glass beads, and the effect may be due to the hot water not in equilibrium having access to more avenues to cooling and freezing than cold water in equilibrium.
* Evaporation: Simulations show that the process always involves a coordinated, well-timed motion of several water molecules.
* Supercooled water: Pure water–free of dust and other impurities on which ice crystals can nucleate–can be supercooled tens of degrees below 0°C without freezing; But below the homogeneous nucleation temperature, around −40°C, the liquid crystallizes almost instantly, no matter the purity.
@ General references: Nagata et al PRL(15) [molecular mechanism of evaporation]; news PT(18)jan [second critical point].
@ Mpemba effect: Jeng AJP(06)jun-phy/05; Ball pw(06)apr; Esposito et al PhyA(07) [and phase transitions in water]; Katz AJP(09)jan [suggested explanation in terms of solutes]; news ns(10)mar [explanation in terms of random impurities]; Brownridge AJP(11)jan [how to observe]; news sn(17)jan [explanation in terms of properties of hydrogen bonds]; Lasanta et al PRL(17) + news pw(17)oct, cosmos(17)nov [modeling in granular fluids]; news ns(20)feb [cooling before heating]; news sn(20)aug [experiment with tiny glass beads].
@ Supercooled water: Debenedetti & Stanley PT(03)jun; Smart PT(18)aug [the 7-year dispute and its resolution].

Ice > s.a. crystals; friction.
* Structures: As of 2009 it has 16 known crystal structures (s.a. the story of ice-IX); 2012, New phase in the 1–5 TPa pressure range, for a total of 17; Close to 0 K, water molecules can't move very well and don't behave the way they do at warmer temperatures; If sprayed onto a platinum surface they tend to stay where they land, and additional molecules stick together wherever they can, forming amorphous ice, in which molecules don't have enough energy to line up to form a crystalline array; Just above 120 K, molecules have a chance to creep around enough to start assembling a proper crystal, with a cubic crystal structure; Common ice with its hexagonal structure is ice Ih (one of the two forms of ice I), and forms above 160 K.
@ References: Choi et al PRL(05) + pn(05)aug [ice at room T with E fields]; Rosenberg PT(05)dec [slipperiness].
@ New forms: news pn(08)jun; news usn(09)sep [ice XV seen in the lab]; Hermann et al PNAS(12) + news cornell(12)jan [new high-pressure phase]; news PhysOrg(13)apr [new phase of superionic ice]; news pt(19)may [at p > 100 GPa, T > 2000 K]; news cosmos(19)may [failed attempt to produce disordered ice].

Special Effects
* High-pressure properties: At 10 GPa it remains frozen up to 320°C! At P > 22 MPa and T > 374°C, beyond the critical point, water turns into a very aggressive solvent, a fact that is crucial for the physical chemistry of Earth's mantle and crust.
@ High-pressure properties: Schwegler et al PRL(00) + news pn(00)mar [freezing]; Knudson et al PRL(12) + Nellis Phy(12) + news sn(12)mar [equation of state]; Sahle et al PNAS(13) [microscopic structure]; news pw(13)mar [one or two metastable liquid phases below 178 K at high pressures?]; news pw(13)mar [just one liquid phase].
@ Warming and shrinking: Cho et al PRL(96) + pn(96)feb; news po(09)jul; Reich TPT(16)jan [exploding water drops].

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