The thermoelectric powers of transition metals at high temperature

Abstract

This paper is concerned with a survey of the experimental data for the thermoelectric power† The thermoelectric power is hereinafter referred to as TEP View all notes of transition metals and with their discussion. For the first time a critical review of the main data, which are given in the literature and proved to be rather incomplete, is presented. When necessary, the author has conducted the TEP measurements within the temperature range of 80° to 1800°k, wherever it was possible. For the first time TEP data have been obtained for scandium, osmium and, effectively, for hafnium; erroneous data for thorium and ruthenium have been corrected; the temperature measuring range for many other metals has been substantially extended. Finally, from the data found in the literature and the new results, a fairly complete notion has been formed of the high-temperature behaviour of TEP for all transition metals (except technetium) in the 3d, 4d, and 5d series of the periodic system, as well as for uranium and thorium. Some empirical regularities in the behaviour of TEP have been detected, the main one of which is that the TEP's of transition metals, which belong to a given column of the periodic table and are in a magnetically disordered state, vary with the temperature above 80°k in a similar way. The paper demonstrates that the TEP of transition metals is characterized by a complex, non-linear temperature dependence. Consequently, the value and sign of the TEP at room temperature cannot serve as a sufficient criterion for characterizing the TEP. The general shape (‘type’) of the TEP temperature curve should be used as the above-mentioned criterion.