Heat capacity of liquid eutectic tellurium alloys

Abstract

Using an adiabatic calorimeter direct measurements of the heat capacity of the liquid Si15Te85, Ge15Te85, Sn15Te85, Pb11Te89, Pb11Te89 and Bi10Te90 alloys and of liquid tellurium have been performed. The heat capacity has been measured as a function of temperature up to about 100 K above the eutectic temperature. The heat capacity decreases with increasing temperature. The excess heat capacity ΔCp of Sn15Te85, Pb11Te89 and Bi10Te90 is pnearly constant within the examined temperature range and is smaller than 5 J mol−1 K−1. ΔCp of Sb11Te89 slightly depends on temperature, while ΔCp of Si15Te85 and Ge15Te85 exhibit large values and temperature dependences. ΔCp reflects the chemical short range order (CSRO) in the liquid state due to the strong compound forming tendency in these alloys. The influence of CSRO is discussed in the light of the measured ΔCp and other structure sensitive properties given in literature.

Critical Review on the Physical Properties of Gallium-Based Liquid Metals and Selected Pathways for Their Alteration

“…We have to point out, however, that excess heat capacities for eutectic compositions may be present. Such excess heat capacities were found for eutectic tellurium alloys, 232 which also reduced heat capacity upon an increase in temperature, inverse to pure metals. Reduction in heat capacity was also found for pure gallium in the liquid state.…”