A Systematic DFT Study on the Optoelectronic and Elastic Characteristics of H-Induced KMnF3 Perovskite

Abstract

Perovskite based compounds have demonstrated unique performance in range of applications. Particularly, KMnF₃ has gained much importance in recent years. However, loading various contents of H ion to be situated at F site would improve the desired physical properties of the pristine KMnF₃. This account carries out density functional theory (DFT) calculations via using CASTEP code. GGA approximation and PW91 functional were adopted to investigate the structural, optoelectronic, and mechanical properties of KMnH_xF_3-x at (x = 0.25 and 0.50). The optimized lattice constants of the pure configuration were in good agreements with the published literature. Moreover, KMnF₃ exhibits a semiconducting nature with a direct electronic band gap of 2.177 eV. The modelled configurations demonstrate negative values of formation energies indicating the possibility of experimental synthesis. The analysed band structure reveals reducing tendency after H insertion. Furthermore, Optical results show an enhancement in the absorption spectra after the insertion of Hydrogen toward visible region of the electromagnetic radiation. Finally, elastic properties have been recorded and suggested that these compounds are mechanically stable. The current findings would significantly contribute in the field of solar cell applications and optoelectronic devices.