First-Principles Investigation of Structural, Elastic, Electronic, and Optical Properties of AcMO3 (M = B, Sc) Perovskites

In this study, a detailed exploration of the structural, elastic, electronic, and optical properties of AcMO3 (M = B, Sc) perovskites is offered, utilizing first-principles calculations with both the generalized gradient approximation (GGA) and modified Becke-Johnson (mBJ) methods. The negative formation and cohesive energies of these compounds confirm their thermodynamic stability. The calculated value of Goldschmidt's tolerance factor is 0.99 for both of the materials, indicating their structural stabilities in cubic phases. The investigations of elastic properties convey AcBO3 to be more resistant to pressure-induced volume changes, shape deformation, and rigid compared to AcScO3. Further, they are found to be brittle in nature and show anisotropic behavior. Additionally, the higher Debye temperature of AcBO3 compared to AcScO3 suggests stiffer atomic bonds and potentially superior thermal conductivity. The electronic structure analysis identifies a direct bandgap of 0.785 eV for AcBO3 and 3.434 eV for AcScO3 within the GGA framework while these values increase to 1.900 and 4.69 eV, respectively, for AcBO3 and AcScO3 with the application of the mBJ method, showing semiconducting nature. Additionally, optical properties analyses convey significant UV absorption, with absorption coefficients far exceeding the respective bandgaps.