Volume dependence of isothermal bulk modulus and thermal expansivity of MgO

A relationship between the isothermal bulk modulus and the isobaric volume expansion for MgO has been used to obtain values for the isothermal bulk modulus at different temperatures up to 3000 K along isobars at selected pressures up to 224 GPa. The volume dependence of the Anderson-Gruneisen parameter, delta(T), has been taken into account under isobaric as well as isothermal conditions. The pressure dependence of thermal expansivity has also been studied along isotherms at selected temperatures up to 3000 K. The method presented here allows the prediction of thermal expansivity and isothermal bulk modulus in the pressure-temperature space, showing a behaviour that is consistent with the available experimental data and ab-initio results. (c) 2005 Elsevier B.V. All rights reserved.