I agree that the tutorial could explain those details a bit bettoer.
- Accumulated Mulliken charge plot: plots the same as the "Net Mulliken Charge" plot above, but in terms of the accumulated Mulliken charge
- The induced charge is calculated in this line in the analysis script:
# Compute the total induced charge on one surface, defining the first 7 atoms as belonging to the left surface
q = [-numpy.cumsum(c-net_charges[0])[7] for c in net_charges]
so the induced charge is calculated as CummulativeSum([Q_i]), where Q_i is a list of mulliken charge difference on all atoms in the left part of the central region wrt the zero-bias charge .