Tellurium vapor pressures were determined by an isopiestic method for solid rhodium-tellurium alloys in the composition range between about 50 and 70 at.% Te and the temperature range between about 650 and 1100°C. Activities and partial molar enthalpies of tellurium were derived from them. The results are interpreted in terms of a statistical-theoretical model, based on a Cr 3 S 4 -type superstructure (with a certain ordering pattern of rhodium vacancies) for Rh 3 Te 4 . The model curve describing the experimental activity data is compatible with the assumption of a continuous transition from the Cr 3 S 4 -type superstructure (at 57.1 at.% Te) through the V 5 Se 8 -type superstructure (at 61.5 at.% Te) to the CdI2-structure (approaching the RhTe2 stoichiometry). All experimental results indicate that the phase relationships shown in the literature [1,2] for this composition range cannot be correct and should be reinvestigated.