A method of calculating volume dependence second and third order Grüneisen parameter for MgO

Abstract

In the paper, we have analyzed the volume dependence Grüneisen parameter of MgO in the different models. The Grüneisen parameter and its logarithmic volume derivatives so called the second (q) and third order Grüneisen parameter (λ) are formulated in the different models. We also introduced the generalized formula from the fitting of experimental data for MgO solids in these models. The experimental initial Grüneisen parameters (γ0) is comparable with the different model of calculations. We perform the calculation of the volume dependence of second and third order Grüneisen parameters according to the different models. The calculated results show the volume dependence of the second order and third order Grüneisen parameters in this case. We found that the parameter q decrease with decreasing volume dependence. We also found that the parameter λ increase with decreasing volume dependence.