Thermoelectric power minimum and electrical resistivity of liquid Hg-based alloys containing Li

The electrical resistivity rho and the thermoelectric power Q of binary liquid Hg-Li alloys have been measured. The resistivity decreases with the addition of Li. This behaviour shows a systematic variation of rho with the addition of solute alkali elements to liquid mercury alloys. As for the other akali amalgams, Q shows a minimum at 5 at.% Li in the curve plotted as a function of the Li concentration at constant temperature. The variation of rho with the addition of alkali elements (including Li) can be well described by the Faber-Ziman theory (1965) based on the nearly free electron model, while the minimum in Q cannot. In order to understand the origin of the minimum in Q of liquid H-Li alloys, higher-order atom-atom correlation function effects seem to be very important, as stressed previously by the present authors for other alkali amalgams such as Hg-Cs alloys. The 'modified Miedema plot' appears to reveal that this higher-order correlation effect is caused by charge transfer from the solute to the Hg atom.