  A large number of water models exists for molecular simulations. They differ
in the ability to reproduce specific features of real water instead of others,
like the correct temperature for the density maximum or the diffusion
coefficient. Past analysis mostly concentrated on ensemble quantities, while
few data was reported on the different microscopic behavior. Here, we compare
seven widely used classical water models (SPC, SPC/E, TIP3P, TIP4P, TIP4P-Ew,
TIP4P/2005 and TIP5P) in terms of their local structure-forming capabilities
through hydrogen bonds for temperatures ranging from 210 K to 350 K by the
introduction of a set of order parameters taking into account the configuration
of the second solvation shell. We found that all models share the same
structural pattern up to a temperature shift. When this shift is applied, all
models overlap onto a master curve. Interestingly, increased stabilization of
fully coordinated structures extending to at least two solvation shells is
found for models that are able to reproduce the correct position of the density
maximum. Our results provide a self-consistent atomic-level structural
comparison protocol, which can be of help in elucidating the influence of
different water models on protein structure and dynamics.
