First-principle Investigation of Structural, Elastic, Electronic and Thermal properties of Dysprosium Hafnate Oxides

摘要

Systematic first-principles calculations based on density functional theory were performed on Dy_2Hf_xO_(3+2x) (x = 0, 1, and 2) compositions. A complete set of elastic parameters including elastic constants, Hill's bulk moduli, Young's moduli, shear moduli and Poisson's ratio were calculated. Analyses of densities of states and charge densities and electron localization functions suggest that the oxide bonds are highly ionic with some degree of covalency in the Hf-O bonds. Thermal properties including the mean sound velocity, Debye temperature, and minimum thermal conductivity were obtained from the elastic constants.