LAUSR

Thermodynamic properties of antimony chalcoiodides have been determined experimentally by means of electromotive force (EMF) method measurements of the$$(- )\;{\text{Sb}}\;({\text{solid}}) / {\text{ionic}}\;{\text{liquid}},{\text{ Sb}}^{3 + } /\left( {{\text{SbXI}} - {\text{SbI}}_{3} - {\text{X}}} \right)\;({\text{solid}})\;( + )$$(-)Sb(solid)/ionicliquid,Sb3+/SbXI-SbI3-X(solid)(+)concentration chains within temperature range 300–430 K (X–S, Se, Te). A mixture of morpholine and formic acid with adding 0.5 mol% anhydrous SbCl3 was used as an electrolyte, whereas equilibrium alloys from the SbXI–SbI3–X three-phase regions of the corresponding systems were exploited as right electrodes. From the EMF measurements, the partial molar functions of antimony in the SbXI–SbI3–I three-phase regions are calculated. The potential formation reactions were determined based on the solid-phase equilibria diagrams of the Sb–X–I systems, and the standard thermodynamic functions of formation and standard entropies of the ternary compounds SbSI, SbSeI, and SbTeI were calculated. For the calculations, the standard thermodynamic functions of SbI3, as well as standard entropies of chalcogens, were used.