STUDY OF THE SORET EFFECT IN MIXED CONDUCTORS BY THE MEASUREMENT OF IONIC AND ELECTRONIC THERMOPOWER

The redistribution of a mobile component in a mixed compound A(1+delta )X(v) in a temperature gradient can be studied by means of time-depend ent measurments of either the ionic of the electronic thermovoltage. T he reduced heat of transport of the mobile componet (Q(A) or Q(X)*) r esults directly from the difference of the partial thermovoltages at t --> 0 and t --> infinity: For materials with predominant ionic conduc tivity, the electronic thermopower hast to be meaured; for materials w ith predominant electronic conductivity, the ionic thermopower has to be measured. Experimental examples are presented.