Thermoelectric Power of AgBr Containing CdBr2

The thermoelectric power of AgBr has been measured as a function of temperature between 100° and 400°C. The measurements have been made on pure material, and also on material doped with CdBr2 in concentrations between 0.01 and 1.0 mole%. The results are compared with the theory of Howard and Lidiard. Satisfactory agreement is obtained if it is assumed that the heats of transport are temperature dependent. The values required for the sum of the heats of transport of the interstitial silver ions and vacancies are —0.57 ev at 175° and —0.69 ev at 250°C.