Equation of State for Simple Minerals

摘要

By the application of the model proposed by the authors in the TFD statistical method for the treatment of equations of state the authors have developed a program for calculating the equation of state of the simple minerals SiO2 and MgO. In the calculation each of the two elements Si and O is assumed to take the form of a sphere with specific radius r(01) and r(02), and is neutral in charge. The Madelung interaction is therefore automatically taken into account. The influence of the periodic lattice field is taken care of by the introduction of the pseudopotentials into the atomic boundaries, in a way similar to that of the previous paper and the two constants A1 and A2 for the pseudopotentials can be evaluated by fitting two pairs of the experimental data (p,v) to the theoretical equations. The equation of state of the mineral can be finally obtained, covering a wide range of pressure from 10 Gpa upward with an accuracy to about 1 to 2% for most part of it.