  We perform extensive Molecular Dynamics simulations of an ensemble of
realistic microgel particles in swollen conditions in a wide range of packing
fractions $\zeta$. We compare neutral and charged microgels, where we consider
charges distribution adherent to experimental conditions. Through a detailed
analysis of single-particle behavior, we are able to identify the different
regimes occurring upon increasing concentration: from shrinking to deformation
and interpenetration, always connecting our findings to available experimental
observations. We then link these single-particle features to the collective
behavior of the suspension, finding evidence of a structural reentrance, that
has no counterpart in the dynamics. Hence, while the maximum of the radial
distribution function displays a non-monotonic behavior with increasing
$\zeta$, the dynamics, quantified by the microgels' mean-squared displacement,
always slows down. Key similarities and differences between neutral and charged
microgels are identified. Importantly, at high enough $\zeta$ we also detect
the fusion of the shells of charged microgels, that was previously invoked to
explain key experimental findings. This highlights the fact that even for
standard poly(N-isopropylacrylamide) microgels, commonly considered as a
prototype of soft colloid, charge effects are relevant. Overall, our study
establishes a powerful framework to uncover the physics of microgel suspensions
under several different conditions. Indeed, it can be readily extended to
tackle different regimes, e.g. high temperature, and systems, e.g. complex
microgel topologies such as ultra-low-crosslinked ones, where experimental
evidence is still limited.
