Physico-Chemical Interaction in the Ag2Se–Zn(Cd, Hg, Pb)Se–SnSe2 Systems

The quaternary compounds AI2BIICIVX4, where AI–Cu, Ag; BII–Zn, Cd, Hg; CIV–Si, Ge, Sn; and X–S, Se, Te, crystallize in non-centrosymmetric structures and may be of interest for nonlinear optics. Here, we present in detail isothermal sections and physico-chemical equilibria in the Ag2Se–Zn(Cd, Hg, Pb)Se–SnSe2 systems where some of these compounds were found. The crystal structure of Ag2ZnSnSe4 was determined for the first time as the tetragonal symmetry, S.G. I4¯2m, lattice parameters a = 0.60434(2), c = 1.13252(5) nm. No quaternary compounds were found in the Ag2Se–PbSe–SnSe2 system. Ag8SnSe6–PbSe is the triangulating section in this system.