Investigating the electronic, optical, elastic, and mechanical properties of cubic CsPbI₃ under varying stress conditions: A computational analysis using density functional theory

This research investigates the electronic, optical, elastic, and mechanical characteristics of cubic Cesium Lead Iodide CsPbI₃ perovskite by utilizing the Generalized Gradient Approximation method under varying stress conditions ranging from 0 to 13$$GPa. Using the Density Functional Theory, the research demonstrates that electronic parameters, such as the electronic band gap, the partial density of states, and the total density of states, are impacted by applied stress. The band gap becomes zero at 14$$GPa. Significant changes are also noted in optical parameters, such as absorption, conductivity, reflectivity, dielectric function, loss function, and refractive index. The study also identifies changes in elastic properties, including elastic constants as well as an exponential rise in mechanical properties, such as Young’s modulus, bulk modulus, and shear modulus. Furthermore, the study finds that Poisson’s ratio, Cauchy pressure, Pugh’s ratio, and Frantsevich’s ratio experience irregular changes. These discoveries provide valuable insights into the properties of CsPbI₃, which could aid in the development of semiconducting devices, transparent coatings, and lenses.