R.M. Ayral

Redetermination of the phase equilibria in the system Tl2Te-Ag2Te

Abstract The Tl 2 Te-Ag 2 Te system phase equilibria have been redetermined by DTA, X-ray diffraction and the measurement of thermoelectric power. The existence of the phase Tl 2 Te was first established and its crystallographic parameters were determined. At least four compounds are formed in the system. The crystallographic parameters of the congruently melting AgTlTe (483°C) and the incongruently melting AgTl 3 Te 2 (382°C), Ag 8 Tl 2 Te 5 (440°C) Ag 5 TlTe 3 (446°C) and Ag 9 TlTe 5 (504°C) were determined. The 0–50 mol% Ag 2 Te range of the system is non-quasi-binary and a narrow solid solution range around the AgTITe composition gives a new insight into its dimorphic transformation.

Limites de stabilité de la phase (Ag, Cu)TlTe dans le système AgCuTlTe

Abstract Three isopleth sections, AgTlTe(CuTlTe), AgTlTeCu2Te, and AgTlTeCu2TlTe2, of the quaternary system AgCuTlTe were investigated using thermal analysis, differential scanning calorimetry, and X-ray powder diffraction. The AgTlTe-based solid solution (AgxCuYTlzTe) limits were determined and the composition-structure relations depicted.