2 research outputs found
Long Distance Correlations in Molecular Orientations of Liquid Water and Shape Dependant Hydrophobic Force
Liquid water, at ambient conditions, has short-range density correlations
which are well known in literature. Surprisingly, large scale molecular
dynamics simulations reveal an unusually long-distance correlation in
`longitudinal' part of dipole-dipole orientational correlations. It is
non-vanishing even at 75 \AA{} and falls-off exponentially with a correlation
length of about 24 \AA{} beyond solvation region. Numerical evidence suggests
that the long range nature of dipole-dipole correlation is due to underlying
fluctuating network of hydrogen-bonds in the liquid phase. This correlation is
shown to give a shape dependant attraction between two hydrophobic surfaces at
large distances of separation and the range of this attractive force is in
agreement with experiments. In addition it is seen that quadrupolar
fluctuations vanish within the first solvation peak (3 \AA{})Comment: 11 pages, 3 figure