Ab-initio Study of Structural, Elastic, Electronic and Vibrational Properties of Pbse in the Rock-salt Structure

Structural, elastic, electronic and vibrational properties of rock-salt PbSe have been investigated theoretically within the framework of density functional theory (DFT). The generalized gradient approximation (GGA) of Perdew, Burke and Ernzerhof (PBE) and revised Perdew-Burke-Ernzerhof (PBEsol) exchange correlation functional. The structure is shown to be mechanically and dynamically stable. The electronic properties show that the compound is a narrow direct band gap semiconductor. The PBE agrees better with the experimental elastic properties while PBEsol agrees better with the experimental structural, electronic and phonon properties.