Structural study of supercritical water. II. Computer simulations

The proton chemical shift of supercritical water is analyzed by computer si mulations with emphasis on its relationship to the number of hydrogen bonds per water molecule and the dipole moment of a water molecule. The chemical shift is shown to be proportional to the number of hydrogen bonds, and the dipole moment of a water molecule at supercritical states is estimated wit hin the simple point charge (SPC)- like and TIP4P-like frameworks of the wa ter intermolecular potential model. The dipole moment can then be used to c onstruct an effective potential model suitable for simulating supercritical water. The radial and orientational correlations in supercritical water ar e examined using the effective potential model. (C) 1999 American Institute of Physics. [S0021-9606(99)51116-1].