The excess enthalpies of liquid In-Bi-Te and Sb-Bi-Te alloys

The excess enthalpies of liquid alloys in the ternary system In-Bi-Te were determined in a heat flow calorimeter for five sections InyBi1-yTe with y = 0.2, 0.4, 0.5, 0.6, and 0.8 at 1.73 K, for the section In0.5Bi0.5-Te at 10 73 K and 973 K. Calorimetric measurements were also performed in the system Sb-Bi-Te for the section Sb0.5Bi0.5-Te at 1173, 1073 and 973 K. The excess enthalpies of the binary and ternary liquid alloys were adapted with the a ssociation model using the Lukas program. Ternary interactions were taken i nto account for the analytical description of both systems. The enthalpy su rface of the systems is characterized by a trough of minima stretching from Bi2Te3 to In2Te3, or Sb2Te3, respectively The numerical values of the exot hermic enthalpies decrease with increasing temperature by dissociation of a ssociates. The decrease is small in the system In-Bi-Te and larger in the s ystem Sb-Bi-Te.