DFT Study of TlSrF3: Structural, Optical, and Thermodynamic Properties

Abstract

Perovskite materials with the general formula ABX₃ have attracted considerable interest due to their broad potential in applications such as optoelectronics, solar energy conversion, and catalysis. In this study, the fluoroperovskite compound TlSrF₃ is theoretically investigated for its suitability for scintillation detector applications. A comprehensive analysis of its structural, electronic, optical, and thermodynamic properties was conducted using density functional theory. The results reveal that TlSrF₃ confirms a stable cubic perovskite phase with the space group Pm-3m (no. 221). The calculated electronic band structure and density of states reveal a direct, wide band gap of approximately 4.40 eV at a high-symmetry point in the Brillouin zone, indicative of strong insulating behavior. Optical properties analyzed over the photon energy range of 0–14 eV show high isotropy between the ε_xx and ε_zz components, significant ultraviolet absorption, and excellent transparency in the visible region — key features for scintillation detection. Thermodynamic stability across wide temperature and pressure ranges is confirmed via the GIBBS2 code calculations. In the absence of experimental data, these theoretical insights offer a reliable foundation for future experimental validation and device-level integration. This work confirms the potential of fluoroperovskites as functional materials in advanced detection and energy technologies.