Investigation of the AgGaS2–PbS and Some Properties of Phases of Variable Composition

Resumo

The quasi-binary section AgGaS₂–PbS in the ternary system Ag₂S–Ga₂S₃–PbS was studied by physicochemical analysis methods (differential thermal, X-ray powder diffraction, and metallographic analyses). The state diagram of the system was constructed, and the quaternary compound AgPb₂GaS₄ was detected to form by a peritectic reaction at 1225 K. Its formation conditions were identified, and its physicochemical properties were investigated. The compound AgPb₂GaS₄ was determined to crystallize in the orthorhombic system with the unit cell parameters a = 8.20 Å, b = 6.84 Å, c = 6.62 Å, and space group Pmn2₁. From the physicochemical analysis data, the existence of narrow ranges of solid solutions based on the initial components was determined.