Thermodynamic Parameters of Lead Sulfide Chrystals in the Cubic Phase

Abstract

Geometric and thermodynamic parameters of cubic PbS crystals were obtained using the
computer calculations of the thermodynamic parameters within density functional theory method
DFT. Cluster models for the calculation based on the analysis of the crystal and electronic
structure. Temperature dependence of energy ΔE and enthalpy ΔH, Gibbs free energy ΔG, heat
capacity at constant pressure CP and constant volume CV, entropy ΔS were determined on the
basis of ab initio calculations of the crystal structure of molecular clusters. Analytical expressions of
temperature dependences of thermodynamic parameters which were approximated with
quantum-chemical calculation points have been presented. Experimental results compared with
theoretically calculated data.