Developed five-site water model. The x axis is perpendicular to the molecular plane, which is represented by the yz plane. The permanent and induced point charges are located on two hydrogen atoms and on two lone pairs of the oxygen atom. The positions of the lone pairs are fixed along the x axis (r OLP = 0.2 Å). The total charge of the H2O molecule is neutralized.
Radial distribution functions of (a) oxygen–oxygen (g OO), (b) oxygen–hydrogen (g OH), and (c) hydrogen–hydrogen sites (g HH) at T = 573 K, p = 280 MPa, and T = 673 K, p = 340 MPa. MD results (solid lines) are compared with experimental neutron diffraction data (dashed lines). 50 High-temperature and high-pressure data are shifted for comparison on the same graph.
(a) Radial distribution functions of oxygen–oxygen sites g OO at T = 673 K and p = 100, 340, 870, and 1190 MPa. MD results (solid lines) are compared with experimental data (dashed lines) for neutron diffraction 50 at 340 MPa and x-ray diffraction data 51 at 870 and 1190 MPa. The pressures for the x-ray diffraction data were calculated by conversion of the density using the IAPWS95 data. 11 High-pressure data are shifted for comparison on the same graph. (b) Running coordination number (rcn) of oxygen–oxygen sites.
(a) Cumulative averages of calculated static dielectric constant of water at p = 2000 MPa and various temperatures. (b) Calculated static dielectric constant of water at various pressures and temperatures. Experimental values 56 are shown as bold lines for comparison. Solid thin lines in (b) indicate fitting curves to the MD results, Eq. (20) .
Distributions of absolute values of molecular dipole moment at p = (a) 340 MPa, (b) 800 MPa, (c) 1500 MPa, and (d) 2000 MPa. Arrows indicate changes in the distributions with increasing temperature.
Mean and standard deviation of dipole moment of H2O calculated by fitting a Gaussian probability density to the distribution of the dipole moment shown in Fig. 6 . Numbers indicate the temperature (K).
(a) Mean intramolecular O-H distances r OH, (b) HOH angles, (c) increased percentage of the |r D| (= |r OH1 + r OH2|), and (d) the contribution of the flexibility of the water molecules into the induced dipole moments. The symbols are the same as those in Fig. 2 . (e) Distribution of intramolecular geometry among r OH and HOH angle at T = 673 K and p = 340 MPa.
Rotational correlation functions (a) C 2 y (t) and (b) C 1 z (t) at p = 2000 MPa and the long-term exponential decay times (c) τ 2 y and (d) τ 1 z .
A comparison of the density at T = 673 K among water models and experiments. 11,49
Radial distribution functions of (a) oxygen–oxygen (g OO), (b) oxygen–hydrogen (g OH), and (c) hydrogen–hydrogen sites (g HH) at T = 673 K and p = 340 MPa. MD results using various water models are compared with experimental neutron diffraction data. 50
Static dielectric constants calculated at T = 673 K using various water models and the experimental data. 56
Potential parameters of the FIPC model.
Parameters relating to the polarization.
Comparison of static dielectric constant of water calculated in this study and experimental values. Experimental values at p = 130, 140, and 340 MPa are derived from interpolation of experimental data. 56
Static dielectric constants calculated using Eq. (20) .
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