  Cluster-assembled metallic films show interesting electrical properties, both
in the near-to-percolation regime, when deposited clusters do not form a
complete layer yet, and when the film thickness is well above the electrical
percolation threshold. Correctly estimating their electrical conductivity is
crucial, but, particularly for the latter regime, standard theoretical tools
are not quite adequate. We therefore developed a procedure based on an
atomically informed mesoscopic model in which ab-initio estimates of electronic
transport at the nanoscale are used to reconstruct the conductivity of
nanogranular gold films generated by molecular dynamics. An equivalent resistor
network is developed, appropriately accounting for ballistic transport. The
method is shown to correctly capture the non-monotonic behavior of the
conductivity as a function of the film thickness, namely a signature feature of
nanogranular films.
