Phase diagram of electrostricted H2O at surfaces of electrodes at 273-373 K: electric critical point of water.
The equation of state of an open system containing water in an electric field of strength E greater than 108 V m-1 leads to a phase diagram with two-phase and single-phase regions in the Pi,E,T coordinates (=electrostriction pressure). The phases differ by their degree of orientation of H2O molecules in the field. The phase transition is discontinuous with respect to E. The calculation shows that the discontinuity vanishes at the critical point: Pi(c) approximately 0.2 GPa, Ec approximately 109 V m-1 and below 313 K. The thermal effect of the transition is calculated and compared with an experiment at the Hg/aqueous electrolyte interface found in the literature.
Danielewicz-Ferchmin
Irena
I
Faculty of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland.
Ferchmin
A Ryszard
AR
D004566:Electrodes; D044367:Phase Transition; D055672:Static Electricity; D013499:Surface Properties; D013696:Temperature; D014867:Water / Q000737:chemistry
D014867:Water