  This paper reviews some selected approaches to the description of transport
properties, mainly electroconductivity, in crystalline and disordered metallic
systems. A detailed qualitative theoretical formulation of the electron
transport processes in metallic systems within a model approach is given.
Generalized kinetic equations which were derived by the method of the
nonequilibrium statistical operator are used. Tight-binding picture and
modified tight-binding approximation (MTBA) were used for describing the
electron subsystem and the electron-lattice interaction correspondingly. The
low- and high-temperature behavior of the resistivity was discussed in detail.
The main objects of discussion are nonmagnetic (or paramagnetic) transition
metals and their disordered alloys. The choice of topics and the emphasis on
concepts and model approach makes it a good method for a better understanding
of the electrical conductivity of the transition metals and their disordered
binary substitutional alloys, but the formalism developed can be applied (with
suitable modification), in principle, to other systems. The approach we used
and the results obtained complements the existent theories of the electrical
conductivity in metallic systems. The present study extends the standard
theoretical format and calculation procedures in the theories of electron
transport in solids.
