The effect of the halide anion on the optical properties of lead halide perovskites

Lead halide perovskites are promising semiconductors for solar energy conversion because of their electronic and optical properties. Using first principles we obtain these properties for the chlorine, bromine and iodine lead halide perovskites. In order to analyze the contributions of the different atoms and orbitals to the absorption coefficient, we split them into a many-species expansion. It allows the atomic and orbital contributions to be identified and quantified as a photon energy function.