  The influence of ordered regions (micro crystallites and aggregates) in the
other wise disordered polymer host matrix on field and temperature dependence
of mobility (\mu) has been simulated. Increase in concentration of ordered
regions leads to increase in magnitude of mobility and in high field regime the
saturation of the mobility occurs at lower electric field strength. The
influence of different mean and standard deviation of Gaussian density of
states (DOS) of ordered regions on the field dependence of mobility was studied
and found to be significant only at higher concentrations. Weak influence of
these parameters at low concentrations are attributed to the strong interface
effects due to the difference in the standard deviation of DOS of two regions
(host and ordered region) and shallow trapping effect by ordered regions. For
all the parameters of ordered regions under investigation the temperature
dependence of mobility (log{\mu}) and the slope of log{\mu} Vs E^{1/2} plot
show 1/T^2 dependence.
