Investigations of Thermal Properties of Earth Mantle Silicates: ASiO₃ (A = Mg, Ca)

Abstract

We have investigated the thermal properties and specific heat of earth mantle silicates ASiO₃ (A = Mg, Ca) by the means of rigid ion model (RIM) and compared them with the earlier experimental reports. The calculated specific heat of ASiO₃ (A = Mg, Ca) obeys T³ law at low temperature (T < θ_D/50). The temperature dependence of the specific heat of MgSiO₃ and CaSiO₃ (0 K ≤ T ≤ 2000 K) is presented along with the elastic, cohesive and thermal properties, like Bulk modulus (B), cohesive energy (φ), molecular force constant (f), reststrahlen frequency (ν), Debye temperature (θ_D) and Gruneisen parameter (γ) at T = 300 K.

Keywords:

• Silicate perovskites
• rigid ion model
• specific heat