Ab-initio Study of Bulk, Slab and Super Cell of Cesium Halide Perovskite

With the remarkable progress seen in perovskite solar cell technology over the past few years, scientists have dedicated significant efforts to exploring the unique characteristics of perovskite halide materials like cspbi3. this particular perovskite exhibits a comparatively higher stability when compared to other inorganic alkaline cations. in other words, given the rapid development of perovskite solar cells in recent years, researchers have paid special attention to studying the properties of perovskite halide materials such as cspbi3. this perovskite is relatively more stable than other inorganic alkaline cations. for this reason, this work is dedicated to the study of the electronic structure of cspbi3 in bulk, super cell and slab modes of this material. for this purpose, the quantum espresso package, which is based on density functional theory, was used. in the first step, a variable cell stability algorithm was implemented to achieve the lowest total energy value and to obtain the optimal grid parameters in bulk mode. also, the ultra-soft quasi-potentials and pbe correlation performance of the quantum espresso site were used as the input file data wherever needed. to examine the surface properties of this perovskite, a three-layer slab with miller 001 indices was designed and fabricated. in other words, the (001) surface of the emerging photovoltaic material cesium lead triiodide (cspbi3) is studied. also, a super cell with dimensions of 2 * 2 * 2 was made and its electronic structure was studied. we found that our results are consistent with those of other works whatever available.