Comparison of Thermodynamic Properties of Simulated Liquid Silica and Water

Abstract
We conduct extensive molecular dynamics computer simulations of a rigid-ion model of liquid silica [L.V. Woodcock et al., J. Chem. Phys. 65, 1565 (1976)], evaluating thermodynamic and transport properties over a wide range of pressure and temperature. We find numerous similarities with behavior found in simulations of supercooled water, including a line of density maxima that passes through a maximum temperature as a function of pressure, and the emergence as temperature decreases of maxima in isotherms of the isothermal compressibility as a function of density.