  We study the structure and dynamics of liquid water in contact with Pd and Au
(111) surfaces using \emph{ab initio} molecular dynamics simulations with and
without van der Waals interactions. Our results show that the structure of
water at the interface of these two metals is very different. For Pd, we
observe the formation of two different domains of preferred orientations, with
opposite net interfacial dipoles. One of these two domains has a large degree
of in-plane hexagonal order. For Au a single domain exists with no in-plane
order. For both metals, the structure of liquid water at the interface is
strongly dependent on the use of dispersion forces. The origin of the
structural domains observed in Pd is associated to the interplay between
water/water and water/metal interactions. This effect is strongly dependent on
the charge transfer that occurs at the interface, and which is not modeled by
current state of the art semi-empirical force fields.
