Investigation of Electronic, Elastic and Dynamic Properties of AgNbO₃ and AgTaO₃ under Pressure: Ab Initio Calculation  

作　　者：Sevket Simsek Sevket Simsek(Department of Material Science and Engineering, Faculty of Engineering, Hakkari University, Hakkari, Turkey)

机构地区：[1]Department of Material Science and Engineering, Faculty of Engineering, Hakkari University, Hakkari, Turkey

出　　处：《World Journal of Condensed Matter Physics》2023年第2期57-77,共21页凝固态物理国际期刊（英文）

摘　　要：Based on the density functional theory within the local density approximation (LDA), we studied the electronic, elastic, and dynamic properties of AgNbO₃ and AgTaO₃ compounds under pressure. The elastic constants, optic and static dielectric constants, born effective charges, and dynamic properties of AgNbO₃ and AgTaO₃ in cubic phase were studied as pressure dependences with the ab initio method. For these compounds, we have also calculated the bulk modulus, Young’s modulus, shear modulus, Vickers hardness, Poisson’s ratio, anisotropy factor, sound velocities, and Debye temperature from the obtained elastic constants. In addition, the brittleness and ductility properties of these compounds were estimated from Poisson’s ratio and Pugh’s rule (G/B). Our calculated values also show that AgNbO₃ (0.37) and AgTaO₃ (0.39) behave as ductile materials and steer away from brittleness by increasing pressure. The calculated values of Vicker hardness for both compounds indicate that they are soft materials. The results show that band gaps, elastic constants, elastic modules, and dynamic properties for both compounds are sensitive to pressure changes. We have also made some comparisons with related experimental and theoretical data that is available in the literature.Based on the density functional theory within the local density approximation (LDA), we studied the electronic, elastic, and dynamic properties of AgNbO₃ and AgTaO₃ compounds under pressure. The elastic constants, optic and static dielectric constants, born effective charges, and dynamic properties of AgNbO₃ and AgTaO₃ in cubic phase were studied as pressure dependences with the ab initio method. For these compounds, we have also calculated the bulk modulus, Young’s modulus, shear modulus, Vickers hardness, Poisson’s ratio, anisotropy factor, sound velocities, and Debye temperature from the obtained elastic constants. In addition, the brittleness and ductility properties of these compounds were estimated from Poisson’s ratio and Pugh’s rule (G/B). Our calculated values also show that AgNbO₃ (0.37) and AgTaO₃ (0.39) behave as ductile materials and steer away from brittleness by increasing pressure. The calculated values of Vicker hardness for both compounds indicate that they are soft materials. The results show that band gaps, elastic constants, elastic modules, and dynamic properties for both compounds are sensitive to pressure changes. We have also made some comparisons with related experimental and theoretical data that is available in the literature.

关 键 词：Electronic Structure Elastic Constants Born Effective Charges Dynamic Properties AgNbO₃ AgTaO₃ 

分 类 号：TG1[金属学及工艺—金属学]