ABSTRACT This study provides complete investigation of electronic, elastic, optical, structural mechanical and thermodynamic characteristics of quaternary mixed‐anion oxyfluorides X ScO 2 F ( X = Ba, Sr, Ca, and Ra) compounds by employing GGA and PBE codes in density functional theory (DFT) method. The determined direct band gaps are reported in the energy range of 1.372 to 3.013 eV by GGA‐PBE approach, while the values are 1.970 to 4.054 eV by hybrid HSE06 approach revealing that all compounds are semiconductors. Moreover, the investigation of thermodynamic properties is performed with the help of density functional perturbation theory (DFPT) method and the estimated zero‐point energy of X ScO 2 F ( X = Ba, Sr, Ca, and Ra) compounds are 0.2977, 0.1826, 0.1910, and 0.2377 eV, respectively. The variation in zero‐point energies reveal that atomic interactions and bond strengths are quite sensitive to all these compounds, as the temperature increases, the heat capacity (C V ) reaches to the Dulong–Petit limit is approximately at 600 K. In XRD, each compound has a distinct diffraction peak and the characteristic peak at 30° which is confirming the tetragonal structure with P4/mmm space group. Optical topologies have predicted the high values of absorption (10 5 ), dielectric function (7–11) and refractive index (2.5–3.5) in the visible and near ultraviolet regions, indicating that these compounds have potential for solar energy applications. All compounds have exhibited the anisotropic behavior in the XY, YZ, and XZ planes, while mechanical properties with their mechanical factor (B/G > 1.75) are verifying their ductility and indicating that they are appropriate for next generation flexible photovoltaic solar cell applications.
Jabeen et al. (Sun,) studied this question.