I use molecular dynamics (MD) simulations to model liquid aluminosilicates at high temperature and high pressure.  From the calculated state properties (e.g., energy, volume, temperature, pressure) of the equilibrium fluid, I develop an equation of state specific to the composition.  Though theoretical in nature, MD simulations are powerful tools for investigating material properties.  For example, I use MD calculations to extract structural information such as coordination numbers.  Comparing coordination statistics directly to thermodynamic properties highlights the influence of microscopic liquid structure on macroscopic properties of liquid silicates.