Application of shell model in molecular dynamics simulation to MgO

The P－V－T equation of state of MgO has been simulated under high pressure and elevated temperature using the molecular dynamics (MD) method with the breathing shell model (BSM). It is found that the MD simulation with BSM is very successful in reproducing accurately the measured molar volumes of MgO over a wide range of temperature and pressure. In addition, the MD simulation reproduces accurately the measured volume compression data of MgO up to 100GPa at 300K. It is demonstrated that the MD simulated P－V－T equation of state of MgO could be applied as a useful internal pressure calibration standard at elevated temperatures and high pressures.