MgSiO 3 perovskite is shown to be a Debye-like mineral by the determination of specific heat, C v , entropy, S, and thermal pressure, Delta P Th , using the Debye theory up to 1800 K. Sound velocities and bulk moduli at ambient conditions published by Yeganeh-Haeri were used to find the ambient acoustic Debye temperature, Theta acD . The variation of Theta acD with T was assumed to be a curve parallel to the Theta acD vs. T curves previously found for Al 2 O 3 , MgO, and MgSiO 3 , enabling Theta acD (T) to be given up to 1800 K. To determine C p , the thermal expansivity, alpha , and the isothermal bulk modulus, K T , are needed. After considering several sets of alpha (T), the alpha (T) data of Funamori and his colleagues were chosen. Using the ambient K T and the values of (theta K T /theta T) P vs. T reported by Jackson and Rigden, K T (T) up to 1800 K was found. Then C P (T) up to 1800 K was found assuming quasiharmonicity in C v . The data behind the C P (T) calculation are also sufficient to find the Gruneisen parameter, gamma (T), and the Anderson-Gruneisen parameters, delta T and delta S , up to 1800 K. The value of q = (theta ln gamma /theta ln V) T was found, and with gamma and rho , Delta P Th vs. V and T was determined. The three sound velocities, v s , v p , and v b = K (sub s/rho ) , were then determined to 1800 K. From v s and v p , Poisson's ratio and the isotropic shear modulus, G, were found to 1800 K. MgSiO 3 perovskite is one of a small, select group of Debye-like minerals for which thermoelastic properties and the equation of state (EOS) are calculable from acoustic data.

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