Physical Chemistry of Aqueous Systems: Meeting the Needs of Industry

ISBN Print: 978-1-56700-034-4

ISBN Online: 978-1-56700-445-8

COMPUTER SIMULATIONS OF SUPERCRITICAL WATER OVER A WIDE RANGE OF DENSITIES

DOI: 10.1615/ICPWS-1994.320
pages 245-252

Abstrakt

Monte Carlo and Molecular Dynamics computer simulations using the rigid TIP4P and the flexible BJH intermolecular water potentials were carried out within the range 573<T<1273 K; 0.02<ρ<1.67 g/cm3; 10<P<10000 MPa. Simulated thermodynamic properties are compared with available experimental data. Under supercritical conditions, an energetic definition of H-bonding is shown to be more effective in separating H-bonded and non-bonded molecular pairs than a widely used geometric definition, whereas a combination of both may be preferable at high densities. Temperature and density dependencies of the simulated intramolecular geometry and vibrational frequencies of BJH water molecules are analysed and compared with IR and Raman spectroscopic measurements.