Theoretical investigations of the physical properties of tetragonal CaSiO3 perovskite

The first principles study of the physical properties of tetragonal CaSiO3 perovskite is reported using the pseudopotential plane wave method within the local density approximation. The calculated equilibrium volume is in good agreement with the available experimental data. A complete elastic tensor of the tetragonal CaSiO3 perovskite is determined in the wide pressure range. The geologically important quantities: sound velocity, Young’s modulus, Poisson’s ratio, and crystal anisotropy, are derived from the calculated data. A systematic decrease of crystal’s anisotropy with pressure is noticed except symmetry plane (001). Finally, by using a quasiharmonic Debye model, the Debye temperature, the heat capacity, the coefficient of thermal expansion, and the Grüneisen parameter are also obtained in the present work.