Thermochemistry of binary liquid alloys of silver with rare earth metals

Abstract

The heats of mixing of binary liquid alloys of silver with barium and lanthanoid metals (La, Ce, Sm, Eu, Gd, Dy and Yb) were determined by isoperibolic calorimetry. The experimental data show the exothermic effects of alloy formation, thus confirming the strong interactions of the components in AgLn melts which increase from divalent (Ba, Eu, Yb) to trivalent metals, and from light to heavy rare earths. The results are discussed on the basis of the effective valence model of rare earths. The associated solution model calculations and characteristic dependence of the entropy of mixing show that these alloys have a short-range order in liquid state.