Insight into Structural, Electronic, Elastic and Optical Properties of Thallium Based Perovskite TlXBr3 (X = Ti, Zr) via DFT Study for Reflective Coating

Perovskites are emerging as key materials for spintronic and optical applications due to their outstanding performance,
stability and eco-friendliness. In this work, a first-principles approach is employed to extensively analyze the structural,
optoelectronic, and elastic properties of TlTiBr3 and TlZrBr3 perovskite compounds. Structural analysis confirms thier
stability in the Fm3̅m (221) space group, while dynamic stability is verified through phonon dispersion curves, showing
that both materials are dynamically stable. Electronic properties reveals that TlTiBr3 and TlZrBr3 exhibits half metallic
nature, further confirmed by density of states. The mechanical stability, anisotropy, and ductility of the compounds are
derived from the obtained elastic constants, indicating that both materials are mechanically stable and have anisotropic
nature. Moreover, the optical properties suggest weak absorption and conductivity. Whereas, they show high reflectivity
in the energy range of 5 eV to 16 eV. They reflect more than 45% of light in this region so it can be concluded that these
materials can be best candidates for reflective coating and spintronic applications.