Investigation of various physical properties of olivine materials Mg2XO4 (X = Si, and Ge): A first principles calculations.

The physical features of cubic-type olivine materials Mg2XO4 (X = Si, and Ge) were studied using an ab-initio method based on density functional theory (DFT). All of our calculated results and earlier theory and experimental results seem to agree with each other pretty well. The mechanical stability of the Mg2XO4 (X = Si, and Ge) compounds has been verified based on the observed elastic stiffness characteristics of both materials. The calculated elastic constants agree with the results from former theoretical studies. It has been discovered that both Mg2SiO4 and Mg2GeO4 compounds are brittle in nature by the analysis of Cauchy pressure, Pugh's ratio, and Poisson's ratio. Young's modulus and hardness values of Mg2SiO4 were the highest among the studied materials, suggesting potential industrial uses such as long-range stress resistance. Analysis of the electronic band structure and density of state of Mg2SiO4 and Mg2GeO4 has proven their insulator characteristics. Ultraviolet energy range (16–26 eV) exhibits high absorption and conductivity, suggesting that the material Mg2XO4 (X = Si, and Ge) may be used as an efficient UV absorber. The materials Mg2XO4 (X = Si, and Ge) that have been studied have a high reflectivity, which makes them acceptable as coating materials. For the first time, calculations and a detailed discussion of the thermodynamic characteristics of Mg2XO4 (X = Si, and Ge) have been performed. These phases have very low thermal conductivity, which means they can be used as thermal barrier coatings (TBC).