A molecular dynamics study of dielectric constant of water from ambient tosub- and supercritical conditions using a fluctuating-charge potential model

Molecular dynamics calculations have been performed based upon a fluctuatin g-charge model TIP4P-FQ over a wide range of state points from ambient to s ub- and supercritical conditions in order to investigate dielectric propert ies of water. The TIP4P-FQ could successfully reproduce the experimental di electric constant. The dielectric constant is dominated not only by the int ermolecular orientational correlation but also by the magnitude of each mol ecular dipole moment. Interesting behavior of these two contributions is re ported as a function of temperature and density. Averaged number of hydroge n bonds has also been found to have a strong correlation with the dielectri c constant. (C) 2001 Elsevier Science B.V. All rights reserved.