  Quantum effects due to the spatial delocalization of light atoms are treated
in molecular simulation via the path integral technique. Among several methods,
Path Integral (PI) Molecular Dynamics (MD) is nowadays a powerful tool to
investigate properties induced by spatial delocalization of atoms; however
computationally this technique is very demanding. The abovementioned limitation
implies the restriction of PIMD applications to relatively small systems and
short time scales. One possible solution to overcome size and time limitation
is to introduce PIMD algorithms into the Adaptive Resolution Simulation Scheme
(AdResS). AdResS requires a relatively small region treated at path integral
level and embeds it into a large molecular reservoir consisting of generic
spherical coarse grained molecules. It was previously shown that the
realization of the idea above, at a simple level, produced reasonable results
for toy systems or simple/test systems like liquid parahydrogen. Encouraged by
previous results, in this paper we show the simulation of liquid water at room
conditions where AdResS, in its latest and more accurate Grand-Canonical-like
version (GC-AdResS), is merged with two of the most relevant PIMD techniques
available in literature. The comparison of our results with those reported in
literature and/or with those obtained from full PIMD simulations shows a highly
satisfactory agreement.
