The electrodynamic features of the multiband model are examined using the
transverse equation of motion approach in order to give the explanation of
several long-standing problems. It turns out that the exact summation of the
most singular terms in powers of 1/ωn leads to the total optical
conductivity which, in the zero-frequency limit, reduces to the results of the
Boltzmann equation, for both the metallic and semiconducting two-band regime.
The detailed calculations are carried out for the quasi-one-dimensional (Q1D)
two-band model corresponding to imperfect charge-density-wave (CDW) nesting. It
is also shown that the present treatment of the impurity scattering processes
gives the DC conductivity of the ordered CDW state in agreement with the
experimental observation. Finally, the DC and optical conductivity are
calculated numerically for a few typical Q1D cases.Comment: 14 pages, 11 figures, to appear in Fizika A (Zagreb
