Entropy for periclase at high compressions and at high temperatures

摘要

We derive a relation for computing volume dependence of entropy at selected isotherms. This formula is based on the Al'tshuler et al. model (J. Appl. Mech. Tech. Phys. 28 (1987) 129) for volume dependence of Grüneisen parameter. The formula for entropy obtained in the present study has been used to determine the results for MgO down to a volume ratio 0.50 at selected isotherms. The obtained results for entropy present a general agreement with those calculated by Cynn et al. (J. Phys. Chem. 99(9) (1995) 7813). We also formulate a relationship between Debye temperature and entropy. And it is found that Debye temperature increases exponentially as entropy decreases.