Electronic structure calculations and optical properties of a new organicinorganic luminescent perovskite: (C_9H_(19)NH _3)_2PbI_2Br_2

摘要

(C_9H_(19)NH_3)_2PbI _2Br_2 compound is a new crystal belonging to the large hybrid organicinorganic perovskites compounds family. Optical properties are investigated by optical absorption UVvisible and photoluminescence (PL) techniques. Bands to band absorption peak at 2.44 eV as well as an extremely strong yellowgreen photoluminescence emission at 2.17 eV is observed at room temperature. First principle calculations based on the DFT and FLAPW methods combined with LDA approximation are performed as well. Density of state close to the gap is presented and discussed in terms of optical absorption and photoluminescence experimental results. The perfect agreement between experimental data and electronic structure calculations is highlighted.