Transport properties of pure metals at high temperatures. II. Silver and gold

Abstract

The high-temperature transport properties of silver and of gold have been determined and are here reported. The measurements extend from 300 to 1100 °K for silver, and from 300 to 1200 °K for gold. Two conclusions are drawn from the measured thermal conductivities and electrical resistivities: (i) the computed Wiedemann–Franz ratio does not reach the standard (Sommerfeld) value, even at the highest temperatures investigated and (ii) the observed temperature variation of these two properties cannot be explained simultaneously on the basis of the Bloch scheme of the free-electron model, or even a generalization thereof. A full discussion of the possible reasons for this behavior will be given in a subsequent paper.New absolute thermoelectric power data for platinum are derived from the measured relative powers of the noble metals; these show considerable deviations from previously reported data, but are believed to be more representative of currently available high purity platinum.