M. Schoen et S. Dietrich, STRUCTURE OF A HARD-SPHERE FLUID IN HARD WEDGES, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics, 56(1), 1997, pp. 499-510
We investigate local structural properties of a hard-sphere fluid expo
sed to periodic arrays of parallel hard wedges by means of grand canon
ical ensemble Monte Carlo simulations. The corrugated substrate is cha
racterized by the dihedral angle gamma of the grooves, the angle 2 pi
- gamma of the tips, and the lateral periodicity length s(x) in the x
direction; gamma is varied over the range pi/2 less than or equal to g
amma less than or equal to pi including a planar wall (gamma=pi) as a
special case. In the second lateral direction y periodic boundary cond
itions are used, whereas confinement in the normal direction z is acco
mplished by two opposite substrates sufficiently far apart. We analyze
the ordering of the fluid within the grooves and at the tips, respect
ively, in terms of the number density rho(x,z;gamma). The crossover be
tween these two regions exhibits pronounced density oscillations. From
the density distribution we extract the excess coverage Gamma(gamma),
which up to now has been known only for gamma = pi; in this special c
ase we find excellent agreement with previous work. Gamma(gamma) is co
mposed of surface and line contribution whose relative magnitude permi
ts us to quantify corrugation effects vs planar confinement.