Ab-initio calculations of the structural, electronic and optical response of KXCl3 (X = be, Ca and Sr) for optoelectronic applications

Ab-initio studies of crystal structure, optoelectronic and mechanical response of potassium-based perovskite KXCl 3 (X = Be, Ca and Sr) compounds have been employed using the quantum based Density Functional Theory (DFT) within the framework of WIEN2K code. The Generalized Gradient Approximation within the scheme of Perdew-Burke- Ernzerhof (PBE-GGA) exchange-correlation approximation is used to calculate the exchange-correlation potential of these compounds. The band structures and Density of States (DOS) are computed by using these approximations. The Band structure and density of state DOS of studied compounds show the wide bandgap semiconductor behavior and these semiconductor materials have indirect band gap semiconductor materials nature. The optical response of the compounds can be checked in terms of the real and the imaginary parts of the dielectric function; and refractive index, extinction coefficient thermal conductivity reflectivity and energy loss function. This frequency dependent optical parameter of studied compounds in the ultraviolet energies region makes them valuable material for optoelectronic devices. Therefore, this potassium based perovskite KXCl 3 (X = Be, Ca and Sr) compounds may be used for the fabrication of a transparent material and optoelectronic devices. . According to Born's criterion, KCaCl 3 is found to be brittle while KBeCl 3 and KSrCl 3 are established as ductile material for different mechanical applications. Finally, theoretically calculated results agree well theoretically and experimental available literature review.