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Abstract
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Molecular dynamics simulations are done
to study the structure and dynamics of hydrogen bonds
(HBs) in water, nanoconfined between parallel graphene
surfaces, at a constant parallel component of
pressure, 101.3 kPa, and at constant temperatures,
ranging from 300 to 390 K. The results indicate that
layering of water molecules beside the surfaces
strongly influences the structure of HBs. Very close
to the surfaces, due to the geometrical restrictions, the
hydrogen atoms of water preferentially orient toward
the surfaces, and hence, scarify their HB network. The
number of HBs per donor, compared to the corresponding
bulk value, is reduced in the organized water
layers beside the surfaces. In contrary, their number is
increased at distances corresponding to the density
profile minima, due to the formation of HBs between
donors and acceptors in the neighboring organized
layers. An analysis of the temperature dependence of
the number of HBs shows that the HBs closer to the
surfaces are weaker than those in the bulk water.
Besides, the entropy change for HB breakage in the
pore is lower than that for the bulk water. The shorttime
behavior of HB dynamics, with a characteristic
time
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