The thermodynamic properties of solid palladium-rich Pd-Cd, Pd-In, Pd-Sn and Pd-Sb alloys

Abstract

Vapor pressure measurements were employed to determine the activities and the free energies of formation, at 1350°K, of palladium-rich Pd-Cd alloys. Entropy of formation values were computed by combining the free-energy data with heats of formation determined calorimetrically at 298°K. Heats of formation at 298°K were determined also for the α-phase palladium-rich alloys of the polyvalent solutes indium, tin, or antimony and for the intermediate phases PdSb and PdSb 2. A comparison of the thermodynamic and electronic properties of the four alloy systems suggests that a correlation exists between them. The major contribution to the heats of formation appears to be derived from a redistribution of electrons upon alloying of palladium.