  In this second part of a series we attempt to construct an empirical model
that can mimick all experimental observations made regarding the role of an
alternative interleaved scan pattern in STEM imaging on the beam damage in a
specific zeolite sample. We make use of a 2D diffusion model that describes the
dissipation of the deposited beam energy in the sequence of probe positions
that are visited during the scan pattern. The diffusion process allows for the
concept of trying to outrun the beam damage by carefully tuning the dwell time
and distance between consecutively visited probe positions. We add a non linear
function to include a threshold effect and evaluate the accumulated damage in
each part of the image as a function of scan pattern details. Together, these
ingredients are able to describe qualitatively all aspects of the experimental
data and provide us with a model that could guide a further optimisation
towards even lower beam damage without lowering the applied electron dose. We
deliberately remain vague on what is diffusing here which avoids introducing
too many sample specific details. This provides hope that the model can be
applied also in sample classes that were not yet studied in such great detail
by adjusting higher level parameters: a sample dependent diffusion constant and
damage threshold.
