Electronic, Mechanical and Thermodynamic Properties of Ceramic Compounds

In this work, we have applied density functional theory (DFT) to study the electronic, mechanical and thermodynamic properties of several ceramic compounds (BN, CaF2 and zirconia). In this regard, we have performed our calculations within local density approximation (LDA) with ultrasoft pseudopotentials (USP). We have computed electronic band structure, phonon density of state, heat capacity, Debye temperature, free energy, entropy and enthalpy. According to obtained results, it is found that (1) zirconia is ductile and BN and CaF2 are brittle compounds, (2) CaF2 is less stable against shear forces than BN and zirconia (3) at high temperatures, it is found that the heat capacity and Debye temperature approach a constant value for all ceramic materials. (4) Our calculation results show that the elastic constants of the ceramic materials are positive. (5) It is found that the details of vibration atoms in BN ceramic can be different because the behavior of its thermodynamics properties is relatively various.