Investigation of the Tl-Sb-S system in the quasi-binary TlSbS/sub 2/-Tl, Tl/sub 2/S-Tl/sub 2/SbS/sub 2/, Tl/sub 2/S-Sb, and TlSbS/sub 2/-Sb sections

The quasi-binary sections of the Tl-Sb-S ternary system were studied by DTA, x-ray crystallographic analysis, microstructural investigations, and microhardness measurement. The TlSbS/sub 2/-Tl section is characterized by the presence of two ternary chemical compounds Tl/sub 4/SbS/sub 2/ and Tl/sub 2/SbS/sub 2/, which melt congruently at 410 and 340/sup 0/C respectively. The Tl/sub 2/S-Tl/sub 2/SbS/sub 2/ section is of the eutectic type. In the Tl/sub 2/S-Sb section we found a compound Tl/sub 4/SbS/sub 2/ which forms a continuous series of solid solutions with Tl/sub 2/S. The Tl/sub 2/SbS/sub 2/-Sb section is of the eutectic type. The interplanar separations were calculated, and the microhardness of Tl/sub 4/SbS/sub 2/ and Tl/sub 2/SbS/sub 2/ was determined. The effect of the replacement of S by Se and of As by Sb was demonstrated.