Theoretical Study on Equation of State of Water at High Temperature and High Densities

MCR theory is applied to calculate the pVT equation of state of H2O molecules system by using a potential function of two molecules with exp-6 type formula. Comparisons with MD simulations show that states of the system may be at solid phase space in such high temperatures of 2 000～4 000 K because of strong attraction between molecules. In this phase area, its thermodynamic properties can not be treated by MCR theory. However, MCR accurately predicts the pVT equation of state of H2O molecules system in higher temperature liquid phase space.