Temperature Dependent Anharmonic Properties of Lead Chalcogenides

Calculations were made to investigate the anharmonic properties of lead chalcogenides PbS, PbSe and PbTe at elevated temperatures by means of primary physical parameters viz. nearest-neighbour distance and hardness parameter using long- and short-range potentials. Higher-order elastic constants are computed up to their melting temperature for these crystals. The first order pressure derivatives of second- and third-order elastic constants, the second-order pressure derivatives of second-order elastic constants and partial contractions are also evaluated at different temperatures. As the experimental elastic constants are not available at high temperatures, hence our results were only compared with the available values obtained at room temperature. The nature of the elastic behaviour in these compounds was analyzed.