Hall coefficient of technically pure metals from 80°K to 800°K

Summary

The Hall coefficients of W, Mo, Ta and Nb are all positive; they are practically independent of temperature for Mo, Ta and Nb, whereasR _H for W rises linearly withT for highT.R _H for Zr is positive and exhibits a maximum at 250°K with a strong decrease on the high temperature side.R _H for Al is negative, increasing (numerically) withT in the whole temperature range. Surveying existing data it becomes clear that there is no simple correspondence between the temperature variation ofR _H and the behaviour of the specific resistance at high temperatures or the electronic structure of the metal. The variation ofr _H (= 1/n*) with the number of conduction electrons is (neglecting all finer details) regular, exhibiting a positive peak (r _H ≅ 2,5) in the middle of thed-band for all three transition groups; interpretation in terms of a two-band model does not seem feasible.