  Bulk dc resistivity and dielectric constant measurements with temperature and
frequency have been performed in LaMn_{1-x}Fe_xO_3 (0 <= x <= 1.0) as a result
of Fe substitution both for the as-synthesized and oxygen annealed samples.
Temperature dependence of real part of dielectric constant at different
frequencies show a frequency and temperature independent value (epsilon_s) at
low temperature for x >= 0.15 where epsilon_0 rises with x reaching a maximum
at x = 0.5 and then it decreases sharply at x = 0.70 showing a further
increasing trend with the further increase in x. The sharp drop of epsilon_s at
x = 0.70 is correlated with the structural change from rhombohedral to
orthorhombic structure. A considerable increase of epsilon_s ~ 43% is observed
for an increase of x from 0.15 to 0.50. Furthermore, epsilon_s is increased
considerably (up to ~ 17% at x = 0.5) due to the oxygen annealing for x <=
0.50. The low temperature resistivities satisfying Variable Range Hopping model
are found to be related with the increase of epsilon_s with x for x <= 0.50.
The analysis of the complex impedance and modulus planes at low temperature
indicates the electrical inhomogeneities in the grain interior of the
compounds.
