Transport theory contribution to the understanding of conductivity in metals

In the transport of conduction electrons different types of scattering interaction can be recognized, with cross-sections that behave differently and give rise to collision frequencies that, in turn, depend on electron momentum with different laws. A few of such diverse collision frequencies are considered, and the ensuing electron distribution functions derived in the framework of the so-called quasi-classical theory with BGK collision term. From the distribution functions conductivities are calculated and the validity of Ohm's law and Matjiessen's rule is investigated in the light of the results obtained.