Interaction of the components in the Ag₂Se–SnSe₂–As₂Se₃ system

Chem. Met. Alloys 1 (2008) 115-119

https://doi.org/10.30970/cma1.0040

O.F. ZMIY, L.D. GULAY, T.A. OSTAPYUK, O.S. KLYMOVYCH

The isothermal section of the quasi-ternary Ag₂Se–SnSe₂–As₂Se₃ system at 520 K was constructed using differential-thermal and X-ray phase analyses. The existence of a quaternary compound, Ag₂SnAs₆Se₁₂ (space group Rm, a = 0.38118(1) nm, c = 3.9724(3) nm) with incongruent type of melting at 690 K, was established. The Se atoms in the structure of the Ag₂SnAs₆Se₁₂ compound are stacked in a close-packed arrangement with the layers in the sequence ABC. A statistical mixture of cations (0.333Ag+0.167Sn+0.500As) occupy one half of the octahedral interstices. The remaining As atoms are distributed over the other octahedral interstices.

Phase diagram of the SnSe₂–As₂Se₃ system (1 - L; 2 – L+SnSe₂; 3 – L+As₂Se₃; 4 – SnSe₂+As₂Se₃).

Keywords

Semiconductors / Phase equilibria / Isothermal section / Crystal structure / X-ray powder diffraction