  Metallic nanogranular films display a complex dynamical response to a
constant bias, showing up as atypical resistive switching mechanism which could
be used to create electrical components for neuromorphic applications. To model
such a phenomenon we use a multiscale approach blending together an ab initio
treatment of the electric current at the nanoscale, a molecular dynamical
approach dictating structural rearrangements, and a finite-element solution of
the heat equation for heat propagation in the sample. We also consider
structural changes due to electromigration which are modelled on the basis of
experimental observations on similar systems. Within such an approach, we
manage to describe some distinctive features of the resistive switching
occurring in nanogranular film and provide a physical interpretation at the
microscopic level.
